Please help
3) a student claims that the reaction of hydrogen and oxygen to form
water is evidence supporting the claim that mass is conserved in a
chemical reaction. the chemical equation the student uses for the reaction
is h2 + o2 --> h2o. does this evidence support the claim? why or why not?*

a.) yes, it supports the claim because all the elements in the reactants appear in the
product.

b.) no, it does not support the claim because it is not a closed system.

c.) yes, it supports the claim because the reaction equation is balanced.

d.) no, it does not support the claim because the reaction equation is not balanced.

Answers

Answer 1

Yes, this evidence supports the claim that mass is conserved in a chemical reaction because the reaction equation is balanced.

This means that the same number of atoms of each element is present in the reactants as in the products. This is the fundamental principle of conservation of mass, which states that mass is neither created nor destroyed during a chemical reaction.

The conservation of mass can also be verified by calculating the total mass of the reactants and comparing it to the total mass of the products.

If the same amount of mass is present in both reactants and products, then the reaction equation is balanced and the conservation of mass is supported.

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Related Questions

A student is collecting data for the reaction of baking soda and vinegar. The initial temperature of the vinegar is 25˚ C and the final temperature of the reaction is 19˚ C. Identify the reaction as endothermic or exothermic and explain what is happening in terms of energy of the systems and the surroundings.

Answers

Answer and explanation:

Based on the temperature change, we can conclude that the reaction of baking soda and vinegar is exothermic. In an exothermic reaction, energy is released from the system to the surroundings in the form of heat, which causes an increase in the temperature of the surroundings.

In this case, the system consists of the baking soda and vinegar, which react to form carbon dioxide gas, water, and sodium acetate. As the reaction proceeds, energy is released from the system to the surroundings in the form of heat. This heat causes an increase in the temperature of the surroundings, which in this case is the surrounding air and any objects in the vicinity of the reaction.

The decrease in temperature from 25˚C to 19˚C indicates that the reaction released energy to the surroundings, and this energy was absorbed by the air and objects in the vicinity of the reaction. This is why the temperature of the surroundings decreases.

Overall, an exothermic reaction like this involves the conversion of potential energy stored in the reactants into kinetic energy in the form of heat, which is released to the surroundings.

14 m3 of gas at a pressure of 3. 0 atmospheres is compressed into a volume of 9. 0 m3. Under what amount of pressure is the sample of gas after the compression?

Answers

The amount of pressure on the sample of gas after compression is 4.67 atm.

The initial volume and pressure of the gas are 14 m³ and 3.0 atm, respectively. After the gas is compressed, its volume becomes 9.0 m³. We can use the combined gas law to determine the final pressure of the gas:

[tex]P_1V_1 / T_1 = P_2V_2 / T_2[/tex]

where[tex]P_1, V_1,\ and\ T_1[/tex]are the Initial pressure, volume, and temperature of the gas, respectively, and [tex]P_2, V_2,\ and\ T_2[/tex] are the final pressure, volume, and temperature of the gas, respectively.

Assuming the temperature is constant, we can simplify the equation to:

[tex]P_2 = (P_1 * V_1) / V_2[/tex]

Substituting the given values, we get:

[tex]P_2[/tex] = (3.0 atm * 14 m³) / 9.0 m³

[tex]P_2[/tex]= 4.67 atm

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How can you prepare 250mL of an aqueous solution using 8. 00g of solid


NaOH?

Answers

To prepare a 250mL aqueous solution using 8.00g of solid NaOH, we will need to dissolve the solid NaOH in water. NaOH is a highly soluble compound, and it readily dissolves in water to form an aqueous solution.

To begin, we need to determine the concentration of the solution we want to prepare. This can be done by calculating the molarity of the solution. Molarity is defined as the number of moles of solute per liter of solution.

To calculate the molarity, we first need to determine the number of moles of NaOH present in the 8.00g of solid. This can be done using the formula:
moles = mass / molar mass

The molar mass of NaOH is 40.00 g/mol (23.00 g/mol for Na and 16.00 g/mol for O and H). Thus, the number of moles of NaOH present in 8.00g of solid is:
moles = 8.00 g / 40.00 g/mol = 0.200 mol

Next, we need to determine the volume of water required to prepare a 250mL solution of this concentration. This can be done using the formula:

moles = concentration x volume
Rearranging the formula, we get:
volume = moles / concentration

The desired concentration is not given, so let's assume we want a 0.5 M solution. Using this concentration and the calculated number of moles, the volume of water required can be calculated as:
volume = 0.200 mol / 0.5 M = 0.400 L or 400 mL


However, we want to prepare a 250mL solution, so we need to adjust the volume of water required. We can do this using the formula:

concentration = moles / volume
Rearranging the formula, we get:
volume = moles / concentration

Plugging in the values, we get:
volume = 0.200 mol / 0.5 M = 0.400 L or 400 mL
To prepare a 250mL solution, we can use 250 mL of water and dissolve the 0.200 mol of NaOH in it. This will give us a 0.8 M solution. We can verify this by calculating the concentration using the formula:

concentration = moles / volume
Plugging in the values, we get:
concentration = 0.200 mol / 0.250 L = 0.8 M

Therefore, to prepare a 250mL aqueous solution using 8.00g of solid NaOH, we need to dissolve the solid in 250mL of water. The resulting solution will have a concentration of 0.8 M.

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A boy kicks a ball with a force of 40 n. at exactly the same moment, a gust of wind blows in the opposite direction of the kick with a force of 40 n.what happened to the ball?

Answers

The ball would experience a net force of 0 N and would not move in either direction.

When the boy kicks the ball with a force of 40 N, he applies a force in one direction. At the same moment, a gust of wind blows in the opposite direction of the kick with a force of 40 N. These two forces act in opposite directions, and therefore cancel each other out.

According to Newton's first law of motion, an object at rest will remain at rest, and an object in motion will continue in motion in a straight line at a constant speed, unless acted upon by a net external force. In this case, the net force on the ball is 0 N, which means that the ball will not move in either direction.

This scenario highlights the importance of understanding net forces when analyzing the motion of objects. In the absence of a net force, the ball will not accelerate, and its velocity will remain constant.

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A solution of lithium carbonate reacts with a solution of potassium iodide to produce solid potassium carbonate and aqueous lithium iodide. You measure 3. 9 moles of potassium carbonate produced by the reaction. How much lithium iodide was produced?

Answers

The quantity of lithium iodide produced in the reaction was determined to be 7.8 moles.

The balanced chemical equation for the reaction between lithium carbonate (Li₂CO₃) and potassium iodide (KI) is:

2 Li₂CO₃ + 2 KI → 2 K₂CO₃ + 4 LiI

From the balanced equation, we can see that for every 2 moles of Li₂CO₃ reacted, 4 moles of LiI are produced.

Therefore, if we have 3.9 moles of K₂CO₃, we can calculate the moles of LiI produced as:

3.9 moles K₂CO₃ × (4 moles LiI / 2 moles Li₂CO₃) = 7.8 moles LiI

Therefore, 7.8 moles of lithium iodide were produced in the reaction.

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A galvanic (voltaic) cell consists of an electrode composed of nickel in a 1. 0 M nickel(II) ion solution and another electrode composed of copper in a 1. 0 M copper(I) ion solution, connected by a salt bridge. Calculate the standard potential for this cell at 25 °C. Refer to the list of standard reduction potentials

Answers

The standard potential for this cell at 25°C is +0.77 V.

We can use the standard reduction potentials to calculate the standard cell potential, which is given by:

E°cell = E°reduction (cathode) - E°reduction (anode)

The reduction half-reactions for nickel and copper ions are:

E°red = -0.25 V for Ni2+(aq) + 2e- Ni(s).

Cu+(aq) + e- → Cu(s) E°red = +0.52 V

Note that we have to use the reduction potential for copper(I) ions, as that is the form in which copper is present in the cell.

When we enter the values into the formula, we obtain:

E°cell = +0.52 V - (-0.25 V)

E°cell = +0.77 V

Therefore, the standard potential for this cell at 25°C is +0.77 V.

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a solution contains 1.30×10-2 m silver nitrate and 6.45×10-3 m lead acetate. solid sodium iodide is added slowly to this mixture. a. what is the formula of the substance that precipitates first?

Answers

To determine the substance that precipitates first, we need to compare the Ksp values for the possible precipitates. The ionic equation for the reaction is:

AgNO3 + Pb(CH3COO)2 + 2NaI → AgI↓ + PbI2↓ + 2NaNO3 + 2CH3COONa

The Ksp expression for AgI is:

Ksp = [Ag+][I-]

The Ksp expression for PbI2 is:

Ksp = [Pb2+][I-]2

The solubility product constant (Ksp) for AgI is 8.5 × 10^-17 and the Ksp for PbI2 is 1.4 × 10^-8.

To determine which substance will precipitate first, we need to compare the Qsp (the reaction quotient) to the Ksp values for AgI and PbI2. At the point of precipitation, Qsp = Ksp.

For AgI:

Qsp = [Ag+][I-] = (1.30×10^-2)(2x) = 2.60x10^-2

For PbI2:

Qsp = [Pb2+][I-]2 = (6.45×10^-3)(2x)^2 = 2.58x10^-2

The substance that will precipitate first is the one with the higher Qsp/Ksp ratio, which is PbI2. Therefore, the formula of the substance that precipitates first is PbI2.

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Now you are ready to explain what happened when Lee mixed sodium and hydrogen chloride. Be sure to use key


concepts in your explanation and provide examples from the Sim or the token activity.


Answer the following question: How did sodium and hydrogen chloride change into two different substances?


pls help

Answers

When Lee mixed sodium and hydrogen chloride, a chemical reaction occurred. Sodium has a single valence electron, which it donates to hydrogen chloride, forming Na⁺ and Cl⁻ ions.

These ions then combine to form solid sodium chloride (NaCl) and hydrogen gas (H₂). This reaction is an example of a redox reaction, where the sodium undergoes oxidation and the hydrogen chloride undergoes reduction.

In the simulation or token activity, the reaction can be represented by the following equation:

2 Na + 2 HCl → 2 NaCl + H₂

Thus, the sodium and hydrogen chloride changed into two different substances, solid sodium chloride and gaseous hydrogen, as a result of a chemical reaction involving the transfer of electrons.

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A drum used to transport crude oil has a volume of 162 L. How many grams of water, as steam, are required to fill the drum at 1. 00 atm and 1069°C? When the temperature in the drum is decreased to 227°C, all the steam condenses. How many mL of water (d = 1. 00 g/mL) can be collected?

Answers

When the steam condenses, we can collect 204.06 mL of water.

To answer this question, we need to use the ideal gas law equation, PV = nRT, where P is pressure, V is volume, n is the number of moles of gas, R is the gas constant, and T is the temperature in Kelvin.

First, we need to convert the given temperature of 1069°C to Kelvin by adding 273.15, giving us 1342.15 K. We can then calculate the number of moles of steam needed to fill the drum by rearranging the ideal gas law equation to solve for n: n = PV/RT.

Plugging in the given values, we get n = (1.00 atm)(162 L)/(0.08206 L·atm/mol·K)(1342.15 K) = 11.32 moles of steam.

To calculate the mass of water in grams, we can use the fact that 1 mole of water weighs 18.015 g. Thus, the mass of water needed to fill the drum as steam is 11.32 moles x 18.015 g/mol = 204.06 g.

When the temperature in the drum is decreased to 227°C, all the steam condenses back into water. The heat released by the steam is given off to the surroundings, and the water vapor loses energy and condenses to form liquid water. We can calculate the volume of water that is formed using the fact that 1 mL of water has a mass of 1.00 g.

Thus, the mass of the water that forms is 204.06 g, which is equivalent to 204.06 mL of water. Therefore, when the steam condenses, we can collect 204.06 mL of water.

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Chemistry 25 Points. Pls explain step by step


4: Calculate the pH of a 0. 25M solution of H3O+ (0. 5pt)


5: Calculate the pH of a 6. 3x10-8M solution of H3O+ (0. 5pt)


6: Look at your answer for 4 and 5 which one is a base? (0. 25pt)


7: Look at 4 and 5; which one is a strong acid?

Answers

4. The pH of the 0.25M solution of H₃O⁺ is 0.602.

5. The pH of the 6.3 x 10⁻⁸M solution of H₃O⁺ is 7.2.

6. Comparing the pH values from 4 and 5, the solution with a pH of 7.2 is a base.

7: Comparing the pH values from 4 and 5, the 0.25M H₃O⁺ solution (pH 0.60) is a strong acid because its pH is much lower than that of the 6.3x10^-8M H₃O⁺ solution (pH 7.20).

Let us learn more in detail.


1. pH: pH is a measure of the acidity or basicity of a solution. It is defined as the negative logarithm of the concentration of hydrogen ions (H⁺) in a solution.

2. H₃O⁺: H₃O⁺ is the hydronium ion, which is formed when a proton (H⁺) is added to a water molecule (H₂O). It is the most common form in which hydrogen ions exist in aqueous solution.

3. Strong acid: A strong acid is an acid that completely dissociates in water, producing a large number of H⁺ ions. Examples of strong acids include hydrochloric acid (HCl) and sulfuric acid (H₂SO₄).

Now, let's tackle the questions:

4. To calculate the pH of a 0.25M solution of H₃O⁺, we can use the following formula:

pH = -log[H₃O⁺]

where [H₃O⁺] is the concentration of hydronium ions in moles per liter. In this case, [H₃O⁺] = 0.25M, so:

pH = -log(0.25) = 0.602

Therefore, the pH of the solution is 0.602.

5. To calculate the pH of a 6.3x10-8M solution of H₃O⁺, we can use the same formula:

pH = -log[H₃O⁺]

In this case, [H₃O⁺] = 6.3x10-8M, so:

pH = -log(6.3x10-8) = 7.2

Therefore, the pH of the solution is 7.2.

6. To determine which solution is a base, we need to look at the pH. pH values below 7 indicate an acidic solution, while pH values above 7 indicate a basic solution. Therefore, the solution with a pH of 7.2 (from question 5) is a base.

7. To determine which solution is a strong acid, we need to consider the concentration of H₃O⁺+ ions. A strong acid is one that completely dissociates in water, producing a large amount of H⁺ ions. Therefore, the solution with a higher concentration of H₃O⁺ ions (from question 4) is a strong acid.

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Dwight has errantly strapped himself to a rocket sled that is now moving at a speed at 100 m/s. If the sled has a total mass of 450 kg and it comes to a stop in 1. 5 seconds, what is the force experienced by the sled and Dwight?

Answers

The force experienced by Dwight and the rocket sled is approximately -30,000 N.

The force can be calculated using the formula :

F = ma

where F is the force,

m is the mass

and a is the acceleration.

Acceleration can be calculated using the formula :

a = v/t

a = (final speed - initial speed) / time
a = (0 m/s - 100 m/s) / 1.5 s
a = (-100 m/s) / 1.5 s
a = -66.67 m/s² (negative sign indicates deceleration)

Calculate the force:
F = ma
F = (450 kg) × (-66.67 m/s²)
F = -30,000 N (approximately)

Thus, the force experienced is -30,000 N. The negative sign indicates the force acts in the opposite direction of the initial motion, as it brings the sled and Dwight to a stop.

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Compare the shape of the carbon chain in a saturated fatty acid, a monounsaturated fatty acid, and a polyunsaturated fatty acid

Answers

The carbon chain in a saturated fatty acid is straight and linear due to single bonds, while the carbon chain in a monounsaturated fatty acid has one bend caused by a double bond, and the carbon chain in a polyunsaturated fatty acid has multiple bends due to multiple double bonds.

Compare the shape of the carbon chain in a saturated fatty acid, a monounsaturated fatty acid, and a polyunsaturated fatty acid.
1. Saturated fatty acid: The carbon chain in a saturated fatty acid contains single bonds between all the carbon atoms. This results in a straight, linear shape, as each carbon atom is fully saturated with hydrogen atoms.

2. Monounsaturated fatty acid: In a monounsaturated fatty acid, the carbon chain has one double bond between two carbon atoms. This double bond creates a bend or kink in the chain, as it results in a decrease in the number of hydrogen atoms bonded to the carbon atoms.

3. Polyunsaturated fatty acid: A polyunsaturated fatty acid contains two or more double bonds between carbon atoms in the chain. Each double bond causes a bend or kink in the chain, similar to the monounsaturated fatty acid. The presence of multiple double bonds leads to a more complex and irregular shape.

In summary, the carbon chain in a saturated fatty acid is straight and linear due to single bonds.

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A canister contains 425 kPa of carbon dioxide, 750 kPa of nitrogen, and 525 kPa of oxygen. What is the total


pressure of the container?

Answers

The total pressure of the container is 1,700 kPa.

The total pressure of the container can be found by adding the individual pressures of each gas.

In this case, we have:

Carbon dioxide (CO₂): 425 kPa

Nitrogen (N₂): 750 kPa

Oxygen (O₂): 525 kPa

To find the total pressure, simply add these values together:

Total pressure = 425 kPa (CO₂) + 750 kPa (N₂) + 525 kPa (O₂)

                        = 1700 kPa

So, the total pressure of the container is 1700 kPa.

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A solution consisting of 11. 4 g NH4Cl in 150 ml of water is titrated with 0. 20 M KOH.



a. How many milliliters of KOH are required to reach the equivalence point?


b. Calculate {Cl-], [K+], and [NH3] at the equivalence point. Assume volumes are additive

Answers

The balanced chemical equation for the reaction between NH4Cl and KOH is:

NH4Cl + KOH → NH3 + KCl + H2O

a. To calculate the volume of 0.20 M KOH required to reach the equivalence point, we need to know the amount of NH4Cl in the solution. The amount of NH4Cl can be calculated as follows:

amount of NH4Cl = (mass of NH4Cl) / (molar mass of NH4Cl)

                = 11.4 g / 53.49 g/mol

                = 0.2131 mol

At the equivalence point, all of the NH4Cl has reacted with the KOH, and the number of moles of KOH added is equal to the number of moles of NH4Cl in the solution. Therefore, we can calculate the volume of KOH required as follows:

moles of KOH = moles of NH4Cl

            = 0.2131 mol

volume of KOH = moles of KOH / Molarity of KOH

             = 0.2131 mol / 0.20 mol/L

             = 1.065 L = 1065 mL

Therefore, 1065 mL of 0.20 M KOH are required to reach the equivalence point.

b. At the equivalence point, all of the NH4Cl has been converted to NH3, K+ and Cl-. Therefore, the concentration of K+ and Cl- will be determined by the amount of KOH added, while the concentration of NH3 will be determined by the amount of NH4Cl initially present. Assuming volumes are additive, the volume of the solution at the equivalence point is 150 mL + 1065 mL = 1215 mL.

The number of moles of K+ and Cl- at the equivalence point can be calculated as follows:

moles of K+ = concentration of KOH × volume of KOH added

           = 0.20 mol/L × 1.065 L

           = 0.213 mol

moles of Cl- = moles of NH4Cl initially present

            = 0.2131 mol

The concentration of K+ and Cl- at the equivalence point can be calculated by dividing the number of moles by the volume of the solution:

[K+] = moles of K+ / volume of solution

    = 0.213 mol / 1.215 L

    = 0.175 M

[Cl-] = moles of Cl- / volume of solution

     = 0.2131 mol / 1.215 L

     = 0.175 M

The concentration of NH3 at the equivalence point can be calculated from the amount of NH4Cl initially present, since all of the NH4Cl has been converted to NH3:

moles of NH3 = moles of NH4Cl initially present

            = 0.2131 mol

The concentration of NH3 can be calculated by dividing the number of moles by the volume of the solution:

[NH3] = moles of NH3 / volume of solution

     = 0.2131 mol / 1.215 L

     = 0.175 M

Therefore, at the equivalence point, [Cl-] = [K+] = 0.175 M, and [NH3] = 0.175 M.

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In a creek bed you find smooth rocks of all sizes. What could explain this?



A. A chemical change has occurred in these rocks.


B. Water has dissolved the outer layers of rocks.


C. When rocks are transported by water, abrasion occurs as they rub and bump into each other.


D. The types of rocks in streams are not as hard as other rocks

Answers

C. When rocks are transported by water, abrasion occurs as they rub and bump into each other.

The presence of smooth rocks of all sizes in a creek bed is most likely explained by the process of abrasion. As water flows over and around the rocks, they can rub and bump against each other, causing the surfaces to wear down and become smoother over time. This is a common occurrence in streams and rivers where the movement of water constantly interacts with the rocks, gradually eroding and smoothing their surfaces.

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Naturally occurring potassium consists of potassium-39 and potassium-41. calculate the percentage of each isotope present if theaverage is 39.1.

Answers

When the average is 39.1, naturally occurring potassium consists of 50% potassium-39 and 50% potassium-41.

An isotope is a variant of an element that has the same number of protons but a different number of neutrons in its nucleus. Potassium has two naturally occurring isotopes: potassium-39 and potassium-41. To calculate the percentage of each isotope present when the average is 39.1, we can use the following formula:

% of potassium-39 = (39.1 - 41) / (39 - 41) x 100%
% of potassium-41 = 100% - % of potassium-39

Using this formula, we can first calculate the percentage of potassium-39:

% of potassium-39 = (39.1 - 41) / (39 - 41) x 100%
% of potassium-39 = -1 / (-2) x 100%
% of potassium-39 = 50%

This means that potassium-39 makes up 50% of the naturally occurring potassium. To calculate the percentage of potassium-41, we simply subtract the percentage of potassium-39 from 100%:

% of potassium-41 = 100% - 50%
% of potassium-41 = 50%

Therefore, potassium-41 also makes up 50% of the naturally occurring potassium. In summary, when the average is 39.1, naturally occurring potassium consists of 50% potassium-39 and 50% potassium-41.

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90 ml of 0.25 m ca(oh)2 are required to titrate 100 ml of carbonic acid. what is molarity of the carbonic acid? assume a 1:1 mole ratio.

Answers

The molarity of the carbonic acid if 90 ml of 0.25 m ca(oh)2 are required to titrate 100 ml of carbonic acid is 0.225 M.

First, we need to write the balanced equation for the reaction between calcium hydroxide (Ca(OH)2) and carbonic acid (H2CO3):

Ca(OH)2 + H2CO3 → CaCO3 + 2H2O

We can see from the equation that there is a 1:1 mole ratio between Ca(OH)2 and H2CO3. Therefore, the moles of Ca(OH)2 used in the titration is equal to the moles of H2CO3 in the solution:

moles of Ca(OH)2 = 0.25 M x 0.090 L = 0.0225 mol

moles of H2CO3 = moles of Ca(OH)2 = 0.0225 mol

Now, we can use the definition of molarity to calculate the molarity of H2CO3:

Molarity = moles of solute / volume of solution

Molarity of H2CO3 = moles of H2CO3 / 0.100 L = 0.0225 mol / 0.100 L = 0.225 M

Therefore, the molarity of the carbonic acid is 0.225 M.

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A specific radioactive isotope is presented for our scientific evaluation for possible use of this isotope within the field of radioisotopic medical tracers. At 1 pm, there are 5. 6 grams and at 7 pm, there are 3. 2 grams. What's the half-life?



A) about 3. 2 hours


B) about 7. 4 hours


c) about 17. 1 hours


D) over 24 hours

Answers

The half-life of the radioactive isotope is B) about 7.4 hours based on the given information of its initial mass at 1 pm and its mass at 7 pm.

To determine the half-life of the isotope, we can use the radioactive decay formula:

[tex]N = N0 * (1/2)^(t/T)[/tex]

where N is the final amount, N0 is the initial amount, t is the time elapsed, T is the half-life.

We can plug in the values given:

N0 = 5.6 g

N = 3.2 g

t = 6 hours (from 1 pm to 7 pm)

T = unknown

[tex]3.2 = 5.6 * (1/2)^(6/T)[/tex]

Solving for T:

[tex](1/2)^(6/T) = 3.2/5.6[/tex]

[tex]ln[(1/2)^(6/T)] = ln(3.2/5.6)[/tex]

[tex](6/T)ln(1/2) = ln(3.2/5.6)[/tex]

[tex]6/T = -0.633[/tex]

T = -9.47 hours

Since the half-life can't be negative, we made a mistake somewhere in the calculations. One common mistake is forgetting to use the natural logarithm (ln) instead of the common logarithm (log). Using the correct logarithm, we get:

[tex]ln[(1/2)^(6/T)] = ln(3.2/5.6)[/tex]

[tex](6/T)ln(1/2) = ln(3.2/5.6)[/tex]

[tex](6/T)(-0.693) = -0.601[/tex]

[tex]T = 6*(-0.693)/(-0.601) = 6*1.151 = 6.906[/tex]

Therefore, the half-life is about 6.9 hours, which is closest to option B) about 7.4 hours.

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given the potential disadvantage caused by the synthesis of fructose-1-phosphate in a liver cell, why is it that an enzyme capable of catalyzing a reaction to convert this form of fructose into glucose has not evolved in a manner similar to the reaction that converts galactose-1-phosphate into glucose-1-phosphate?

Answers

Fructose-1-phosphate is an intermediate in fructose metabolism and is produced by fructokinase. While fructose-1-phosphate can be converted to glucose in the liver via the enzyme fructose-1,6-bisphosphatase, this reaction requires energy and is irreversible.

The potential disadvantage of the synthesis of fructose-1-phosphate is that it traps fructose in the liver cell, which can lead to the formation of advanced glycation end products (AGEs) that are associated with various diseases. However, the conversion of fructose-1-phosphate to glucose would require an enzyme that is specific to  reaction, which may not have evolved in same way as the galactose-1-phosphate to glucose-1-phosphate reaction. It is also possible that  evolutionary advantage of being able to metabolize fructose outweighs the potential disadvantage of the formation of AGEs.

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Which of these is an unsaturated solution? choose all that apply.
o 50 g of kci in 50 g of water at 90°c
60 g of nh4cl in 100 g of water at 80°c
o 70 g of nh3 in 100 g of water at 20°c
50 g of nh4cl in 100 g of water at 60°c
80 g of kno3 in 100 g of water at 60°c
o 60 g of kl in 50 g of water at 10°c

Answers

C. 70 g of NH₃ in 100 g of water at 20°c and E. 80 g of KNO₃ in 100 g of water at 60°c An unsaturated solution is one that contains less solute than a saturated solution.

What is water?

Water is a transparent, tasteless, odorless, and nearly colorless chemical substance. It is a compound of two hydrogen atoms and one oxygen atom and is essential for the survival of all known forms of life. Water is an essential resource for human and ecological health, making it one of the most important substances on Earth. Water is found naturally in oceans, rivers, lakes, and streams, and can also be found in the air, in the form of water vapor. Water is also found in the form of ice and snow, and is found in the soil, in aquifers and underground. Water is a renewable resource, but due to human activity and climate change, it is becoming increasingly scarce in many parts of the world.

In all of the above examples, the amount of solute (KCl, NH₄Cl, NH₃, KNO₃, and KL) is less than the amount that would be needed to create a saturated solution. Therefore, all of the above solutions are unsaturated.

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Complete Question:
Which of these is an unsaturated solution? choose all that apply.

A. 50 g of kci in 50 g of water at 90°c

B. 60 g of nh4cl in 100 g of water at 80°c

C. 70 g of nh3 in 100 g of water at 20°c

D. 50 g of nh4cl in 100 g of water at 60°c

E. 80 g of kno3 in 100 g of water at 60°c

F. 60 g of kl in 50 g of water at 10°c

If 15.0 ml of a 0.300 m aluminum phosphate solution reacts with 180 mg of magnesium metal according to the following equation, what mass of aluminum metal will be produced?

Answers

The mass of aluminum metal produced when 15.0 mL of a 0.300 M aluminum phosphate solution reacts with 180 mg of magnesium metal is 15.60 mg.


1. First, find moles of aluminum phosphate using its concentration and volume: moles = M x V = 0.300 mol/L x 0.015 L = 0.0045 mol.


2. Next, convert the mass of magnesium metal to moles using its molar mass: moles = mass / molar mass = 180 mg / (24.31 g/mol x 1000 mg/g) = 0.00741 mol.


3. Now, find the limiting reactant by comparing the mole ratios: (0.0045 mol AlPO₄) / (2) < (0.00741 mol Mg) / (3), so aluminum phosphate is the limiting reactant.


4. Calculate the moles of aluminum produced using the mole ratio: moles of Al = 2 x 0.0045 mol AlPO₄ = 0.009 mol.


5. Finally, convert the moles of aluminum to mass: mass = moles x molar mass = 0.009 mol x 26.98 g/mol x 1000 mg/g = 15.60 mg.

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When 4 g of a metal carbonate MCO, was dissolved in 160 cm of 1 M hydrochloric acid and then the resultant solution diluted to one litre, 25. 0 cm of this solution required 20. 0 cm' of 0. IM sodium hydroxide solutidn for complete neutralisation, calculate:
(i) The number of moles per litre of excess hydrochloric acid that reacted with sodium hydroxide, NaOH.

(ii) The number of moles per litre of acid that reacted with the carbonate.

(iii) The number of moles of carbonate, MCO, that reacted with the acid.

(iv) The formula mass of the carbonate, MCO, (v) The atomic mass of the metal M. (C = 12. 0. 0 = 16. 0)​

Answers

(i) The number of moles per litre of excess hydrochloric acid that reacted with sodium hydroxide, NaOH, is 0.2.

(ii) The number of moles per litre of acid that reacted with the carbonate is 0.04.

(iii) The number of moles of carbonate, MCO, that reacted with the acid is 0.008.

(iv) The formula mass of the carbonate, MCO, is the sum of the atomic masses of the carbon, oxygen and metal atoms, i.e., MCO, M + 12 + 16 = M + 28.

(v) The atomic mass of the metal M can be determined by subtracting 28 from the formula mass of the carbonate. Thus, M = formula mass of MCO - 28.

In summary, the given information is used to calculate the number of moles per litre of excess hydrochloric acid, the number of moles per litre of acid that reacted with the carbonate, the number of moles of carbonate that reacted with the acid, the formula mass of the carbonate and the atomic mass of the metal.

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NEED HELP FAST!!!! Please answer both questions

Answers

There is a 0.37 M molarity.

1.71 m molality is present.

Molarity: What is it?

The quantity of a solute in a solution is measured in terms of molarity, a unit of concentration. It is described as the quantity of solutes that dissolve in one liter of solution, or mol/L. Molarity, in other words, reveals how many moles of solute there are in a liter of solution.

To determine molarity, use the following formula:

Molarity (M) is calculated as moles of solute divided by the liters of solution.

100g/180 g/mol * 1/1.5 L is the molarity.

= 0.37 M,

Molality = 200g/58.5g/mol * 1/2 Kg

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Explain why the combustion of biomass releases no net carbon into the atmosphere

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Biomass is organic matter that comes from recently living plants and animals. When biomass is burned, it releases carbon dioxide into the atmosphere.

However, this carbon dioxide was originally absorbed from the atmosphere by the plants as they grew, meaning that the combustion of biomass releases no net carbon into the atmosphere. This is because the carbon released during combustion is balanced out by the carbon that was absorbed during the biomass's growth phase. This is in contrast to burning fossil fuels, which release carbon that has been locked away for millions of years, leading to a net increase in atmospheric carbon dioxide. Therefore, the use of biomass as a renewable energy source can be a carbon-neutral option for reducing greenhouse gas emissions.

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Drag and drop the words that accurately complete the chart below. Example a lion and a cheetah mistletoe on a tree a coyote eating a rabbit a remora and a shark clownfish and anemone parasitism friendship competition Type of Symbiosis mutualism 1:10 predation relationship commensalism collaboration alliance​

Answers

Answer:

Lion and cheetah - Competition

Mistletoe on a tree - Parasitism

Coyote eating rabbit- Predatation

Remora and Shark - Mutualism

Clownfish and Anemone - Relationship

Explanation:

How much liquid chlorine to add to pool calculator.

Answers

The amount of liquid chlorine to add to a pool will depend on the size of the pool, current chlorine levels, and other factors such as temperature, sunlight exposure, and bather load.

The most accurate way to determine how much liquid chlorine to add to your pool is by testing the current chlorine levels using a pool testing kit, and following the recommended dosage on the liquid chlorine product based on your pool size and current chlorine levels.

You can also consult a pool professional for assistance with determining the proper amount of liquid chlorine to add to your pool.

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5. use the chemical equation and the table to answer the question.
pb(no3)2(aq) + 2kbr(aq) → pbbr2(s) + 2kno3(aq)
reactant or product molar mass (g/mol)
pb(no3)2 331
kbr 119
pbbr2 367
kno3 101
when 496.5 grams of pb(no3)2 reacts completely with kbr, how much will the total mass of the products be?

a 496.5 g
b 550.5 g
c 702.0 g
d 853.5 g

Answers

The total mass of the products formed is 1529.89 g or approximately 1530 g. The correct answer is option C, 702.0 g

To determine the mass of the products formed, we first need to determine the limiting reactant in the reaction. To do this, we can calculate the number of moles of each reactant:

Number of moles of [tex]Pb(NO3)2[/tex] = 496.5 g / 331 g/mol = 1.5 mol

Number of moles of [tex]KBr[/tex] = 496.5 g / 119 g/mol = 4.17 mol

From the balanced chemical equation:

[tex]Pb(NO3)2(aq) + 2KBr(aq) → PbBr2(s) + 2KNO3(aq)[/tex]

We can see that 1 mol of[tex]Pb(NO3)2[/tex] reacts with 2 mol of [tex]KBr[/tex] to produce 1 mol of [tex]PbBr2[/tex]. Therefore, since we have 1.5 mol of [tex]Pb(NO3)2[/tex]and 4.17 mol of [tex]KBr, KBr[/tex] is the limiting reactant.

Now we can use the stoichiometry of the balanced chemical equation to calculate the mass of the product formed:

1 mol of [tex]PbBr2[/tex]has a mass of 367 g/mol, so 4.17 mol of [tex]PbBr2[/tex] has a mass of:

4.17 mol x 367 g/mol = 1529.89 g

Therefore, the total mass of the products formed is 1529.89 g or approximately 1530 g. The correct answer is option C, 702.0 g, is not correct.

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A 24. 59 g mixture of zinc and sodium is reacted with a stoichiometric amount of sulfuric acid. The reaction mixture is then reacted with 97. 7 mL of 4. 79 M barium chloride to produce the maximum possible amount of barium sulfate. Determine the percent sodium by mass in the original mixture. G

Answers

A mixture of 24.59 g zinc and sodium was reacted with H₂SO₄ and then with BaCl₂ to form BaSO₄. The percentage of sodium by mass in the mixture was found to be 16.97%.

The first step is to determine the amount of barium sulfate formed in the reaction. From the reaction equation, we can see that 1 mole of barium sulfate is produced for every mole of zinc in the mixture. Therefore, the amount of barium sulfate formed is:

24.59 g Zn x (1 mol Zn / 65.38 g Zn) x (1 mol BaSO₄ / 1 mol Zn) x (233.39 g BaSO₄ / 1 mol BaSO₄) = 8.80 g BaSO₄

Next, we need to calculate the amount of sodium in the original mixture. We can do this by subtracting the mass of zinc from the total mass of the mixture:

Mixture mass - Zinc mass = Sodium mass

24.59 g - (24.59 g x %Zn) = Sodium mass

We don't know the percent zinc by mass, but we can find it using the mass of barium sulfate formed. The mass percent of sodium in the mixture is then:

%Na = (Sodium mass / Mixture mass) x 100

To find the percent zinc by mass, we can subtract the percent sodium by mass from 100:

%Zn = 100 - %Na

Finally, we can substitute the values we found into the equations and solve for %Na:

8.80 g BaSO₄ x (1 mol BaSO₄ / 233.39 g BaSO₄) x (1 mol Na₂SO₄ / 1 mol BaSO₄) x (142.04 g Na₂SO₄ / 1 mol Na₂SO₄) = 4.04 g Na₂SO₄

Mixture mass - Zinc mass = Sodium mass

24.59 g - (24.59 g x %Zn) = Sodium mass

%Na = (Sodium mass / Mixture mass) x 100

Substituting the values we found:

%Na = (4.04 g / 24.59 g) x 100 = 16.4%

Therefore, the percent sodium by mass in the original mixture is 16.4%.

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A 5. 00-g sample of aluminum pellets (Cs = 0. 89 J/g°C) and a 10. 00-g sample of iron pellets (Cs= 0. 45 J/g°C) are heated to 100. 0°C. The mixture of hot iron and aluminum is then dropped into an unknown mass of water (Cs= 4. 18 J/g°C) at 22. 0°C. The final temperature of the water and metals mixture is 23. 7°C.


How much heat (in J) is transferred to the water by aluminum pellets?


I am confused how to determine the mass of water

Answers

The amount of heat transferred to the water by the aluminum pellets is 382.87 J

To determine the mass of water, you can use the equation:

q = m x Cs x deltaT

where q is the amount of heat transferred, m is the mass of the substance (in this case, the water), Cs is the specific heat capacity of water, and deltaT is the change in temperature.

Using the final temperature of 23.7°C and the initial temperature of 22.0°C, we get:

deltaT = 23.7°C - 22.0°C = 1.7°C

We can plug in the values for the iron and aluminum pellets:

q = (5.00 g x 0.89 J/g°C x (100.0°C - 23.7°C)) + (10.00 g x 0.45 J/g°C x (100.0°C - 23.7°C))

q = 345.67 J + 347.85 J

q = 693.52 J

Now, to find the mass of water, we can rearrange the equation and solve for m:

m = q / (Cs x deltaT)

m = 693.52 J / (4.18 J/g°C x 1.7°C)

m = 97.1 g

Therefore, the mass of water is 97.1 g. To find how much heat is transferred to the water by the aluminum pellets, we need to subtract the heat transferred by the iron pellets from the total heat transferred:

q_aluminum = q_total - q_iron

q_aluminum = 693.52 J - (10.00 g x 0.45 J/g°C x (100.0°C - 23.7°C))

q_aluminum = 693.52 J - 310.65 J

q_aluminum = 382.87 J

Therefore, the amount of heat transferred to the water by the aluminum pellets is 382.87 J.

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Air enters the body through the ________ and travels down the ________ to the lungs. the ______ contracts to allow space for the _________ to take in air. then, the ______ relaxes causing the _____ to release air.

Answers

Air enters the body through the nose or mouth and travels down the trachea or windpipe to the lungs.

The diaphragm contracts to allow space for the lungs to take in air. Then, the diaphragm relaxes causing the lungs to release air.

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They include information about their problems or concerns in a way that makes people sympathize.How is the above passage organized? A. classification B. definition C. cause and effect D. comparison and contrast According to Mazahua UDHR, what is the frequency of all letters from most to least common? 5. Understanding the IRR and NPVThe net present value (NPV) and internal rate of return (IRR) methods of investment analysis are interrelated and are sometimes used together to make capital budgeting decisions. Consider the case of Cold Goose Metal Works Inc. :Last Tuesday, Cold Goose Metal Works Inc. Lost a portion of its planning and financial data when both its main and its backup servers crashed. The companys CFO remembers that the internal rate of return (IRR) of Project Lambda is 11. 3%, but he cant recall how much Cold Goose originally invested in the project nor the projects net present value (NPV). 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