Outline why there is no limit to the number of control variables that an experiment can have.

Answers

Answer 1

Most experimental designs measures solely one or two variables at a time. Any different factor, which could probably impact the results, should be efficaciously controlled.

Why is it vital to restriction the number of variables in an experiment?

Controlling variables is important due to the fact mild variations in the experimental set-up ought to strongly have an effect on the result being measured.

Can an scan have extra than one controlled variable explain?

Controlled variables are portions that a scientist needs to remain constant. If they had been altered, it would appreciably have an effect on the experiment's results. Most experiments have extra than one controlled variable.

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Related Questions

14.87 moles of Magnesium should form 14.87 moles of Magnesium Chloride. 14.77 moles of Hydrochloric acid should form 7.97 moles of Magnesium Chloride. Only 1.78 moles of Magnesium chloride is obtained. What is the percent yield?
PLEASE HELP and teach please

Answers

According the question the Percent yield is 11.99%

What is yield?

Yield is an economic term referring to the income generated by an investment over a period of time. It is usually expressed as a percentage of the initial investment and is calculated by taking the total income earned and dividing it by the initial investment. Yield is an important measure of the performance of an investment, and is a key factor in determining the attractiveness of an investment. Yields can be calculated for individual investments, or for portfolios of investments. Yields can also be calculated for different types of investments, such as stocks, bonds, and mutual funds. Yields are also used to compare investments with different levels of risk, so investors can make informed decisions about their investments. Yields are affected by a variety of factors, including interest rates, inflation, and market conditions.

The percent yield can be calculated using the formula:

Percent yield = (Actual yield / Theoretical yield) * 100

For Magnesium Chloride, the theoretical yield is 14.87 moles, and the actual yield is 1.78 moles.

Therefore, the percent yield is:

Percent yield = (1.78 / 14.87) * 100 = 11.99%

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A balanced chemical equation allows one to determine the

A) mechanism involved in the reaction.

B) electron configuration of all the elements in the reaction.

C) energy released in the reaction.

D) mole ratio of any 2 substances in the reaction

Answers

The correct option is D) mole ratio of any 2 substances in the reaction.

A balanced chemical equation describes the identities and quantities of the reactants and products involved in a chemical reaction. It specifies the number of molecules or moles of each substance required and produced in the reaction.

                   The coefficients can determine the mole ratio of any two substances involved in the reaction in a balanced equation. This information is critical for predicting how much product can be obtained from a given amount of reactant or determining the limiting reactant in a reaction.

                    Knowing the mole ratio also allows for precise stoichiometric calculations, which can be used in various chemical applications such as synthesis, chemical analysis, and industrial processes.

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Marble (calcium carbonate) reacts with hydrochloric acid solution to form calcium
chloride solution, water and carbon dioxide. What is the percent yield of carbon dioxide
if 3. 65 g of the gas is collected when 10. 0 g marble reacts?

Answers

The percent yield of carbon dioxide if the 3.65 g of the gas is collected when the 10.0 g marble reacts is react with the HCl is 83 %.

The chemical reaction is as follows :

CaCO₃ (aq)  +  2HCl (aq) ----> CaCl₂ (aq)  + H₂O (l) + CO₂(g)

The mass of the CaCO₃  = 10 g

The molar mass of the CaCO₃  = 100.09 g/mol

The moles of the CaCO₃  = 10 / 100.09

The moles of the CaCO₃  = 0.0999 mol

The molar ratio of the carbon dioxide and the calcium carbonate = 1 : 1

The moles of the carbon dioxide = 0.0999 mol

The mass of the carbon dioxide = moles × molar mass

The mass of the carbon dioxide = 0.0999 × 44

The mass of the carbon dioxide = 4.40 g

The percent yield = ( actual yield / theoretical yield ) × 100 %

The percent yield = ( 3.65 / 4.40 ) × 100 %

The percent yield = 83 %

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3. Predict the change in electronegativity of the next elements in a row (C, Si), then check those properties. Do they match your predictions?

Answers

The elements which come after 'C' and 'Si' are 'Ge' and 'Sn'. The element 'F' is the most electronegative element. Down the group the electronegativity generally decreases.

What is electronegativity?

The electronegativity of an atom is defined as the relative tendency or power of the bonded atom in a molecule to attract the shared pair of electrons towards itself.

In general the electronegativity decreases on moving down a group. The increase in the size of atoms and the shielding effect of inner electrons decreases the electronegativity.

Here 'Ge' and 'Sn' comes below 'C' and 'Si'.

Thus the electronegativity of the elements after 'C' and 'Si' decreases.

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In which way is primary succession similar to secondary succession?

Both occur where life already exists.
Both are gradual.
Both occur where no life exists.
Both involve creating soil

Answers

Primary succession and secondary succession are similar in that they are both gradual processes and involve the creation of soil.

What is Primary succession and secondary succession?

Primary succession occurs in an area where no soil or living organisms are present, such as on bare rock or after a volcanic eruption. Over time, pioneer species like lichens and mosses establish themselves, eventually leading to the growth of small plants, shrubs, and trees. As these organisms die and decompose, they create soil, which allows for the growth of larger and more complex organisms. This process can take hundreds or even thousands of years.

Secondary succession, on the other hand, occurs in an area where soil and some living organisms are already present, but the community has been disturbed or destroyed, such as after a forest fire, a landslide, or human activity like clear-cutting or farming. The process begins with the growth of fast-growing and weedy species that quickly colonize the area, followed by the establishment of more complex and longer-lived species. Secondary succession is generally faster than primary succession because soil and some organisms are already present.

Primary succession and secondary succession are similar in that they are both gradual processes and involve the creation of soil.

However, they differ in terms of the starting point of the succession. Primary succession begins on bare rock or soil that has never been colonized by living organisms, while secondary succession begins on soil that has previously supported life but has been disturbed, such as after a forest fire or clear-cutting.

Therefore, the statement "Both occur where no life exists" is only true for primary succession, while "Both occur where life already exists" is only true for secondary succession.

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When 12 moles of O₂ reacts with 1.1 mole of C10H8 what is the limiting reactant? C10H8 + 12 O₂ -> 10 CO₂ + 4H₂O​

Answers

Answer:

O₂

Explanation:

A limiting reactant is the reactant that runs out first in a reaction.

Oxygen

To find the limiting reactant, we can find how many reactions will occur with the given amount of reactant. To do this we can divide moles of the reactant by moles per reaction. If the reaction occurs 1 time, we say that 1 mol of reaction is created. So, the reactant that forms fewer moles of reaction is the limiting reactant.

Moles of reaction = [tex]\displaystyle \frac{12molO_{2} }{1}*\frac{1molrxn}{12mol_{2} }[/tex]= 1 mol[tex]_{rxn}[/tex]

This means that with 12 moles of oxygen, 1 full reaction will occur (1 mol of reaction).

Naphthalene (C₁₀H₈)

Now, we can do the same equation with Naphthalene. If it creates fewer moles of reaction, then it is the limiting reactant. If not, then oxygen is the limiting reactant.

Moles of reaction = [tex]\displaystyle \frac{1.1molC_{10}H_{8} }{1} *\frac{1molrxn}{1molC_{10}H_{8}}[/tex] = 1.1 mol[tex]_{rxn}[/tex]

This means that 1.1 moles of Naphthalene will create 1.1 mol of reaction.

Limiting Reactant

The math above shows that the amount of oxygen given will only create 1 mol of reaction, while the Naphthalene forms 1.1 mols of reaction. Thus, oxygen is the limiting reactant because it creates fewer moles of reaction.

A 25. 00 mL sample of an aqueous solution of Ba(OH)2 requires 18. 45 mL of 0. 01500 M HCl (aq) for its neutralization. What is the molarity of the Ba(OH)2?

Answers

The molarity of the 25 mL Ba(OH)₂ solution required to neutralize 18.45 mL  0.01500 M HCl solution is 0.005535 M.

The balanced chemical equation for the reaction between Ba(OH)2 and HCl is:

Ba(OH)2 + 2HCl -> BaCl2 + 2H2O

The moles of HCl used can be calculated as:

moles of HCl = concentration of HCl x volume of HCl

moles of HCl = 0.01500 M x 0.01845 L

moles of HCl = 0.00027675 mol

Since the stoichiometry of the reaction is 1:2 between Ba(OH)2 and HCl, the moles of Ba(OH)2 can be calculated as:

moles of Ba(OH)2 = 0.00027675 mol / 2

moles of Ba(OH)2 = 0.000138375 mol

The molarity of Ba(OH)2 can be calculated as:

molarity of Ba(OH)2 = moles of Ba(OH)2 / volume of Ba(OH)2

molarity of Ba(OH)2 = 0.000138375 mol / 0.02500 L

molarity of Ba(OH)2 = 0.005535 M

Therefore, the molarity of Ba(OH)2 is 0.005535 M.

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Why we need to use the archetorien principle in lab report

Answers

This principle is important in laboratory reports because it can be used to determine an object's or material's density, which is an important physical property used in many applications.

The Archimedes' principle is a fundamental physics principle that states that the buoyant force acting on an object submerged in a fluid equals the weight of the fluid displaced by the object. It is critical to use the Archimedes' principle in a lab report to accurately and precisely determine the density of the object or material being studied. This principle provides a dependable and accurate method for calculating density, which is useful in many scientific and engineering fields. By including the Archimedes' principle in a lab report, you show that you considered all relevant factors and used appropriate methods to determine the physical properties of the materials being studied.

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you have 5L of a stock solution of 6M AgNO3, you need a 3M AgNO3 strength solution for a lab assignment. What volume of 3M could you make from the stock solution.

Answers

The volume of 3M from making stock solution is 7.5 liters.

To make a 3M solution from a 6M stock solution of AgNO3, we need to add water to the stock solution. Let us assume x liters of 3M solution from 5 liters of the 6M stock solution.

The amount of AgNO3 in the 5 liters of the stock solution is:

5 L * 6 mol/L = 30 mol AgNO3

To make a 3M solution, we need:

3 mol/L * x L = 3x mol AgNO3

We can use the formula:

C1V1 = C2V2

where,

C1 = concentration of the stock solution

C2 = concentration of the final solution

V1 = volume of stock solution

V2 = volume of the final solution

In this case, we know that:

C1 = 6 M

C2 = 3 M

V1 = x

V2 = 5 L + x

In this case, we know that:

C1 = 6 M

C2 = 3 M

V1 = x

V2 = 5 L + x

let us substitute the above values in the formula

6 M * V1 = 3 M * (5 L + x)

Solving for x, we get:

x = 2.5 L

Therefore, to make a 3M solution from a 6M stock solution, a final volume of 5 + 2.5 = 7.5 liters to get a 3M solution.

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2. When a bubble escapes form a sunken ship, it has a volume of 12.0ml at a pressure of 400.0 atm. and a temp.. of -3.00°C. It reaches the surface where the pressure is 1.10 atm. and the temperature is 27.0°C. What is its new volume? ( round the answer to nearest tens for sig figs)

Answers

Answer: 4848.22 mL

Explanation:

V2= P1V1T2/(T1 P2)  = (400.00 X 12.0 X 300.15)/(270.15 x 1.10)

For parts of the free-response question that require calculations, clearly show the method used and the steps involved in arriving at your answers. You must show your work to receive credit for your answer. Examples and equations may be included in your answers where appropriate. 2 NO₂(g) +F₂(g) → NO₂F(g) AH-284 kJ/mol,zn NO₂(g) and F₂ (g) can react to produce NO₂F(g), as represented above. A proposed mechanism for the reaction has two elementary steps, as shown below. Step 1: NO₂+ F₂ NO₂F + F (slow) Step 2: NO₂+F NO₂F (fast)

(a) Write a rate law for the overall reaction that is consistent with the proposed mechanism.​

Answers

Rate law for the overall reaction that is consistent with the proposed mechanism is k [NO₂] [F₂].

What is rate law expression?

It is an expression that provides a relationship between the rate of the reaction and the concentrations of the reactants participating in it multiplying with rate constant. Rate in rate law expression is decided according to slow step.

Example-

If a  reaction given as  A + B → C    rate constant = k

rate = k [A] [B]

Given,

Step 1: NO₂+ F₂ → NO₂F + F (slow)

Step 2: NO₂+F → NO₂F (fast)

rate = k [NO₂] [F₂]

Therefore, rate law for the overall reaction that is consistent with the proposed mechanism is k [NO₂] [F₂].

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5. A scientist mixed two samples together: a white
solid that boils at about 800°C and a colorless gas
that boils at about 70°C. He analyzed the results and
found two ending substances. One of the ending
substances boils at 245°C. This ending substance is
made up of the repeating group of atoms shown
above. Which of the diagrams to the left shows the
repeating groups of atoms that make up the
samples the scientist mixed together?

Answers

The starting material can be shown by the image in image B

What is a chemical reaction?

A chemical reaction is a process that involves the conversion of one or more substances (called reactants) into new substances (called products) through the breaking and forming of chemical bonds. In a chemical reaction, the original chemical properties of the reactants are changed, resulting in the formation of one or more new substances with different properties.

Chemical reactions can involve the combination of two or more substances to form a single product, the decomposition of a single substance into two or more products, or the exchange of atoms or groups of atoms between reactants to form new products.

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How many mol of CaSO3 were left after the water was driven off? To answer this, What is the molar mass of 1 mol of CaSO3?
Multiply the molar mass of 1 mol times the mass 7.00g to get mol.

Answers

There are 5 mol of CaSO3 were left after the water was driven off.

What is molar mass ?

The molar mass is the substance; it helps to determine the mass of the sample substance to the atom of the sample or substance. The molar mass depends on the molecular formula and the isotopes of the atom. Molar mass is used for the inducement of electric charge. Molar mass is the measurement of the volume of the mass.

What is moles?

A mole is the atom's elementary particle, an ion. The mole of the substance is always related to the Avogadro number. The mole is always associated with the weight or mass of the element or substance. The standard unit of a mole is mol. The mole is a significant factor of the reactant and products to form an equation. A mole calculates the atom, ion, and substance weighs.

Therefore,  are 5 mol of CaSO3 were left after the water was driven off.

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When a force is applied to an object, what happens?

The object changes its color.
The object changes its shape.
The object changes its motion.
The object changes its state.

Answers

When a force is applied to an object, the object changes its state. Therefore, the correct option is option D.

What is force?

A force is an effect in physics that enables the movement of something with mass that change its velocity and accelerate. It may represent a push or perhaps a pull, with the direction and magnitude always present, making this one a vector quantity. It really is measured in newtons (N) and is denoted by the sign F.

Newton's second law, in its original form, states that perhaps the net force exerted on an object is equivalent to the pace that its momentum varies with time. When a force is applied to an object, the object changes its state.

Therefore, the correct option is option D.

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Falling oil prices would significantly lower the cost of production for many goods. Producers of
plastic kayaks, for instance, would be able to produce larger quantities of their product given the
decrease in input costs. Which of the following illustrates how consumers respond to the price
incentive brought about by the subsequent increase in supply? (1 point)
O Falling prices lead consumers to purchase fewer kayaks.
O Falling prices lead consumers to purchase more kayaks.
O Rising prices lead consumers to purchase fewer kayaks.
O Rising prices lead consumers to purchase more kayaks.
M
4
18

Answers

A consumer is known as a person who purchases the product for his or her own need and uses that product. Here Falling prices lead consumers to purchase more kayaks. The correct option is B.

What is fall in price?

The general decrease in the price of products as well as in the economy is defined as the fall in price. The falling prices occur for many reasons including supply and demand factors.

A decrease in demand and an increase in supply will cause a fall in equilibrium price, but the effect on equilibrium quantity cannot be determined.

Thus the correct option is B.

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If the brine contains 138 g of NaCl, how much Cl2 can be produced?

Answers

Answer:

167.5g

Explanation:

From the question, we know the mass of NaCl and the molar mass of NaCl, so we can calculate the number of moles of NaCl:

Moles = mass ÷ molar mass

The molar mass of NaCl can be calculated by adding the relative formula masses of the elements Na and Cl:

23.0 + 35.5 = 58.5

We can use the formula to find the number of moles of NaCl:

moles = 138 ÷ 58.5

= 2.35897...

Now, we need to find the mass of Cl2. Rearranging the formula of moles = mass ÷ molar mass

mass = moles × molar mass

Calculating the molar mass of Cl2 by adding the relative atomic masses:

35.5 + 35.5 = 71

Hence the mass is:

2.35897... × 71 = 167.5g (to 1dp)

How many liters of oxygen gas (at STP) are needed to burn 0.277L butane?

Answers

Explanation:

Refer to pic..........

How many grams are in 4.50x1023 molecules of CO2? [Molar mass CO2 = 44.01 g/mol CO2]
7.48x10-11 g CO2

32.9 g CO2
44.01 g CO2

6.16x1045 g CO2

Answers

The mass of 4.5 moles of CO2  is 7.48x10-11 g CO2  Option b)

What are 4 types of moles mass?

The ratio between the mass and the quantity of material (measured in moles) of any sample of a chemical compound is known as the molar mass (M) in chemistry.  The molar mass of a material is a bulk characteristic rather than a molecular one. The compound's molar mass is an average over many samples, which frequently have different masses because of elements.

A terrestrial average and a result of the relative frequency of the isotopes of the component elements on Earth, the molar mass is most frequently calculated from the standard atomic weights. For changing between a substance's mass and quantity in bulk amounts, the molar mass is the proper unit.

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Which of the following is false?


The orbits defined in the Bohr model of an atom for atoms in the first and second period. But, beyond those atoms, the model no longer is appropriate.


The dual nature of an electron prevents simultaneously knowing both the exact location and the velocity of the electron.


The Schrödinger equations take into account the dual nature of an electron to define regions in space where electrons have a high probability of being located.


The more precisely the location of an electron is known, the less precisely the velocity is known.

Answers

Answer:

B is the false one

hope it helps u u u BRAINLIST

What major type of weak interactions can asp have that are absent in chymotrypsin?

Answers

In the catalytic cycle, asp is capable of weak interactions with histidine that chymotrypsin does not have.

Throughout the catalytic cycle, Asp-102 maintains its negative charge. It establishes a salt bond with the protonated form of His-57 but not the deprotonated form, stabilizing the protonated form and boosting the histidine's affinity for protons.

The histidine residue interacts with aspartate and is oriented correctly as a result. Following that, histidine and serine's alcohol group may interact. Histidine changes serine from a weak nucleophile (alcohol) into a strong nucleophile by removing the hydrogen ion from the alcohol (alkoxide).

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Identify the Name, Symbol, number of protons, neutrons, and electrons in a neutral atom of each of the following: (Please refer to a periodic table):

Answers

Answer:

Carbon

Name: Carbon

Symbol: C

Number of protons: 6

Number of neutrons: 6 or 7 (Carbon has two stable isotopes with 6 or 7 neutrons)

Number of electrons: 6

Sodium

Name: Sodium

Symbol: Na

Number of protons: 11

Number of neutrons: 12 or 13 (Sodium has one stable isotope with 12 neutrons, and another with 13 neutrons)

Number of electrons: 11

Helium

Name: Helium

Symbol: He

Number of protons: 2

Number of neutrons: 2

Number of electrons: 2

Chlorine

Name: Chlorine

Symbol: Cl

Number of protons: 17

Number of neutrons: 18 or 20 (Chlorine has two stable isotopes with 18 or 20 neutrons)

Number of electrons: 17

Gold

Name: Gold

Symbol: Au

Number of protons: 79

Number of neutrons: 118 (Gold has only one stable isotope with 118 neutrons)

Number of electrons: 79

Another student points out that Jasmine’s calculation relates only to the water. The student wonders if it is possible to determine the amount of energy in the sample of Cheetos.

Explain why you can answer part (A), even though the calculation in Question 4 related only to the water. In your explanation, refer to evidence from the experiment and appropriate chemical laws.

Answers

In Question 4, Jasmine calculated the amount of energy absorbed by the water when the burning Cheeto was placed in it. Although the calculation related only to the water, we can still determine the amount of energy released by the burning Cheeto. This is because of the Law of Conservation of Energy, which states that energy cannot be created or destroyed, only transferred or transformed from one form to another. In this case, the energy released by the burning Cheeto is transferred to the water, causing its temperature to increase.

Therefore, we can use the amount of energy absorbed by the water (calculated in Question 4) as a measure of the amount of energy released by the burning Cheeto. We can assume that the energy released by the Cheeto is equal to the energy absorbed by the water. This is known as the principle of calorimetry, which states that the heat lost by the object being studied is equal to the heat gained by the surrounding medium.

However, it is important to note that this assumption is only valid if all the energy released by the Cheeto is transferred to the water. In reality, some energy may be lost to the surroundings, such as through radiation or conduction. Therefore, the calculated value for the energy released by the Cheeto may be slightly lower than the actual value.

PLEASE HELP!!
Classify each reaction as synthesis, decomposition, single replacement, double
replacement, or combustion.
>
NaOH + CuSO4 → Na2 SO4 + Cu(OH)2

C12H22O11 + O2CO2 + H₂O

NH4NO3 → N₂O + H₂O

BaCl2 + Na2 SO4 → BaSO4 + NaCl

1. synthesis
2. decomposition
3.single
4double displacement
5.combustion

Answers

Answer:

NaOH + CuSO₄ → Na₂SO₄ + Cu(OH)₂ is a double displacement reaction

C₁₂H₂₂O₁₁ + 12O₂ --> 12CO₂ + 11H₂O. This is a combustion reaction, as it involves a fuel reacting with oxygen to form carbon dioxide and water. However, this is not a balanced equation and so I have added in the correct ratios to balance the equation.

NH₄NO₃ → N₂O + 2H₂O. This is a decomposition reaction, as it involves the compound ammonium nitrate, 'decomposing' or breaking down into smaller components: dinitrogen oxide and water

BaCl₂ + Na₂SO₄ → BaSO₄ + 2NaCl. This is a double replacement reaction

What is the mass of 2.007 moles of propane gas, C3H8?

Answers

Answer:

To calculate the mass of 2.007 moles of propane gas (C3H8), we need to first determine its molar mass.

The molar mass of propane (C3H8) can be calculated as:

3(C) + 8(H) = (3 x 12.01 g/mol) + (8 x 1.01 g/mol) = 44.11 g/mol

Therefore, the mass of 2.007 moles of propane is:

Mass = 2.007 moles x 44.11 g/mol = 88.46 g

So, the mass of 2.007 moles of propane gas (C3H8) is 88.46 g.

What mass og MgO is neded to produce 9. 38g of Na2O?

2NaCl+MgO=Na2O+MgCl2

Answers

The 6.10 g of MgO (Magnesium oxide) is needed to produce 9.38 g of Na2O(Sodium oxide).

To solve this problem, we need to use stoichiometry to relate the mass of Na2O produced to the mass of MgO used.

From the balanced chemical equation:

2 NaCl + MgO → Na2O + MgCl2

We can see that 1 mole of MgO produces 1 mole of Na2O. We can use the molar mass of Na2O to convert the given mass of Na2O to moles:

9.38 g Na2O x (1 mol Na2O / 61.98 g Na2O) = 0.1514 mol Na2O

Since 1 mole of MgO produces 1 mole of Na2O, we know that we need 0.1514 mol MgO to produce 0.1514 mol Na2O. Using the molar mass of MgO, we can convert this to mass:

0.1514 mol MgO x (40.31 g MgO / 1 mol MgO) = 6.10 g MgO

Therefore, 6.10 g of MgO is needed to produce 9.38 g of Na2O.

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Note: The question would be as

What mass of MgO is neded to produce 9. 38g of Na2O?

2NaCl+MgO=Na2O+MgCl2

Which statement best describes a pure substance? *
It has three visible phases.
It has constant physical properties.
It is heterogeneous.
It has variable composition.

Answers

The statement which best describes a pure substance is that it has constant physical properties which is therefore denoted as option B.

What is a Pure substance?

This is referred to as a single kind of matter that cannot be separated into other kinds of matter by any physical means.

This type of sample of matter has both definite and constant composition and distinct chemical properties and is referred to as being homogeneous in nature with no form of impurities which is therefore the reason why it was chosen a the correct choice.

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21 The diagram shows an experiment. A B blue litmus paper D aqueous ammonium chloride What happens to the pieces of litmus paper? + aqueous sodium hydroxide blue litmus paper changes colour changes colour no colour change no colour change SHIRED heat red litmus paper changes colour no colour change changes colour no colour change red litmus paper​

Answers

Three is no change in the blue litmus but the red litmus change color. This is because the ammonia turns red litmus blue due to ammonia.

What is the reaction of ammonium chloride and sodium hydroxide?

When ammonium chloride and sodium hydroxide are mixed, they undergo a neutralization reaction to form ammonium hydroxide and sodium chloride. The chemical equation for this reaction is:

NH4Cl + NaOH → NH4OH + NaCl

In this equation, NH4Cl represents ammonium chloride, NaOH represents sodium hydroxide, NH4OH represents ammonium hydroxide, and NaCl represents sodium chloride.

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Calculate the expected vapor pressure (in atm) for a solution prepared by dissolving 183. 0 g fructose in 500. 0 ml of water. Fructose is a nondissociating molecule, with a molar mass

Answers

The expected vapor pressure of the solution prepared by dissolving 183.0 g of fructose in 500.0 mL of water is approximately 0.0301 atm.

The mole fraction of water in the solution can be calculated as follows:

Moles of water = (volume of water in liters) x (density of water) / (molar mass of water)

Moles of water = (500.0 mL / 1000.0 mL/L) x (0.9982 g/mL) / (18.015 g/mol)

Moles of water = 27.722 mol

Moles of fructose = (mass of fructose) / (molar mass of fructose)

Moles of fructose = 183.0 g / 180.16 g/mol

Moles of fructose = 1.016 mol

The total moles of solute and solvent in the solution are:

Total moles = moles of water + moles of fructose

Total moles = 27.722 mol + 1.016 mol

Total moles = 28.738 mol

The mole fraction of water in the solution is:

Mole fraction of water = moles of water / total moles

Mole fraction of water = 27.722 mol / 28.738 mol

Mole fraction of water = 0.962

Using Raoult's Law, the expected vapor pressure of the solution can be calculated as:

Vapor pressure = mole fraction of water x vapor pressure of pure water

Vapor pressure = 0.962 x 0.0313 atm

Vapor pressure = 0.0301 atm

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How is s,p,d,f blocks related to the type of element and its properties?

Answers

grouping elements into s, p, d, and f blocks allows us to predict the chemical and physical properties of elements based on their electron configurations and periodic table positions.

The periodic table's s, p, d, and f blocks refer to the arrangement of electrons in the atom's outermost energy level (valence shell), and they are related to the element's type and properties in several ways.

Atomic size increases from right to left within a period and from top to bottom within a group.

Ionization Energy: The energy required to remove an electron from an atom is referred to as ionisation energy.

Electronegativity: The ability of an atom to attract electrons towards itself in a chemical bond is measured by electronegativity.

Reactivity: An element's reactivity is determined by the number of valence electrons it possesses. Because the s-block elements have one or two valence electrons, they are extremely reactive.

Chemistry: Ionic compounds are formed by s-block elements with nonmetals, whereas covalent compounds are formed by p-block elements.

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1. Mr. Bryan's pet turtle walks 280 feet at a speed of 4ft/min. How long does his walk take? Do not forget to write the word "minutes" after your calculation.

type answer



2.Adrian's mom drove 3 hours to get to San Antonio at a speed of 65 miles per hour (mph). How far away is San Antonio? Do not forget your units- write the word "miles" at the end of your calculation.


Type answer

Answers

Answer: 1. is 70 minutes

2. is 195

Explanation: I took the test and I got a B but for sure it's this

It would take Mr. Bryan's pet turtle 70 minutes to walk 280 feet at a speed of 4 feet per minute.

To calculate the time it takes for Mr. Bryan's pet turtle to walk 280 feet at a speed of 4 feet per minute, we can use the formula:

time = distance / speed

Plugging in the given values, we get:

time = 280 feet / 4 ft/min = 70 minutes

Therefore, it would take Mr. Bryan's pet turtle 70 minutes to walk 280 feet at a speed of 4 feet per minute.

The second one is:

According to the given data:

distance = speed x time

where speed is given as 65 miles per hour (mph) and time is given as 3 hours.

Plugging in these values, we get:

distance = 65 mph x 3 hours = 195 miles

Therefore, San Antonio is 195 miles away from Adrian's mom.

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