The starch tests negative in Benedict's assay even though it contains a reducing group, the answer is as follows:Starch tests negative in Benedict's assay even though it contains a reducing group because the reducing group is not exposed due to the molecule's highly branched structure.
Benedict's assay is used to test for reducing sugars, which are monosaccharides or disaccharides that have a free carbonyl group that can reduce copper ions in the reagent to form a red precipitate.
However, the glucose units in starch are joined together by alpha glycosidic bonds, which link the anomeric carbon of one glucose molecule to the hydroxyl group of another glucose molecule, forming a highly branched structure.
This structure makes it difficult for Benedict's reagent to react with the reducing groups in the glucose units, resulting in a negative test.
Therefore, even though starch contains a reducing group, it will not test positive in Benedict's assay due to its highly branched structure that hides the reducing group.
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calculate the maximum mass of the sodium soap that can be prepared from 195 g of glyceryl trimyristate.
We must ascertain the molar mass of glyceryl trimyristate and the stoichiometric ratio of the reactants and products in the saponification reaction in order to calculate the maximum mass of sodium soap that may be produced from 195 g of glyceryl trimyristate.
The saponification of glyceryl trimyristate with sodium hydroxide (NaOH) produces three molecules of sodium soap and one molecule of glycerol:
Glyceryl trimyristate + 3 NaOH → 3 sodium soap + glycerol
The molar mass of glyceryl trimyristate is calculated as:
3 (myristic acid molar mass) + (glycerol molar mass) = 3 (228.39 g/mol) + 92.09 g/mol = 913.26 g/mol
The stoichiometric ratio of the reactants and products is 1:3, which means that for every one mole of glyceryl trimyristate, three moles of sodium soap are produced.
To calculate the maximum mass of sodium soap that can be prepared, we need to convert the given mass of glyceryl trimyristate to moles using its molar mass and then use the stoichiometric ratio to determine the maximum mass of sodium soap that can be produced:
Number of moles of glyceryl trimyristate = 195 g / 913.26 g/mol = 0.214 moles
Number of moles of sodium soap produced = 3 × 0.214 moles = 0.642 moles
Mass of sodium soap produced = number of moles × molar mass of sodium soap = 0.642 moles × 278.38 g/mol = 178.46 g
Therefore the correct answer is the maximum mass of the sodium soap that can be prepared from 195 g of glyceryl trimyristate is 178.46 g.
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Given the following equation:
2H2O --> 2H2 +O2
What mass of oxygen would form from 5 moles of water?
Question 6 options:
.078
320
.3125
80
how many liters of 0.100 m hcl would be required to react completely with 5.00 grams of calcium hydroxide?
The balanced chemical equation for the reaction between hydrochloric acid (HCl) and calcium hydroxide (Ca(OH)2) is:
2HCl + Ca(OH)2 → CaCl2 + 2H2O
First, we need to calculate the moles of calcium hydroxide (Ca(OH)2) present in 5.00 grams:
molar mass of Ca(OH)2 = 40.08 + 2(15.99) + 2(1.01) = 74.10 g/mol
moles of Ca(OH)2 = mass / molar mass = 5.00 g / 74.10 g/mol = 0.0674 mol
According to the balanced chemical equation, 2 moles of HCl react with 1 mole of Ca(OH)2. Therefore, the number of moles of HCl required to react completely with 0.0674 mol of Ca(OH)2 is:
moles of HCl = 2 x moles of Ca(OH)2 = 2 x 0.0674 mol = 0.1348 mol
Finally, we can use the molarity (0.100 M) and the number of moles of HCl to calculate the volume of the HCl solution required:
moles = molarity x volume (in liters)
volume (in liters) = moles / molarity = 0.1348 mol / 0.100 mol/L = 1.35 L
Therefore, 1.35 liters of 0.100 M HCl are required to react completely with 5.00 grams of calcium hydroxide.
1.35 liters of 0.100 M [tex]HCl[/tex] would be required to react completely with 5.00 grams of calcium hydroxide.
To determine how many liters of 0.100 M [tex]HCl[/tex]would be required to react completely with 5.00 grams of calcium hydroxide, follow these steps:
1. Write the balanced chemical equation for the reaction:
[tex]2 HCl(aq) + Ca(OH)₂(s) → CaCl₂(aq) + 2 H₂O(l)[/tex]
2. Calculate the moles of calcium hydroxide (Ca(OH)₂):
Molar mass of [tex]Ca(OH)₂ = 40.08 (Ca) + 2 * (16.00 + 1.01) (2 * OH) = 74.10 g/mol[/tex]
Moles of[tex]Ca(OH)₂[/tex] = mass / molar mass =[tex]5.00 g / 74.10 g/mol ≈ 0.0675 mol[/tex]
3. Determine the stoichiometry between[tex]HCl[/tex] and[tex]Ca(OH)₂[/tex] from the balanced equation:
2 moles of [tex]HCl[/tex] react with 1 mole of [tex]Ca(OH)₂[/tex].
4. Calculate the moles of[tex]HCl[/tex] required to react completely with[tex]Ca(OH)₂[/tex]:
Moles of [tex]HCl = 0.0675 mol Ca(OH)₂ * (2 mol HCl / 1 mol Ca(OH)₂) = 0.135 mol HCl[/tex]
5. Determine the volume of 0.100 M[tex]HCl[/tex]needed to provide the required moles of[tex]HCl[/tex]:
Volume = moles of[tex]HCl[/tex] / molarity = 0.135 mol / 0.100 M = 1.35 L
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a sample of neon is at 89c and 123 kpa. if the pressure changes to 145 kpa and the volume remains constant, what is the new temperature, in c?
The new temperature of the neon gas is 151.45°C when the pressure changes to 145 kPa and the volume remains constant.
Assuming that the amount of neon gas remains constant, we can use the combined gas law to find the new temperature. The combined gas law states that:
(P1 x V1) / T1 = (P2 x V2) / T2
where P1, V1, and T1 are the initial pressure, volume, and temperature, respectively, and P2, V2, and T2 are the final pressure, volume, and temperature, respectively. We are given P1 = 123 kPa, T1 = 89°C = 362 K, V1 = V2 (since the volume remains constant), and P2 = 145 kPa. Substituting these values into the combined gas law equation gives:
(123 kPa x V) / 362 K = (145 kPa x V) / T2
Simplifying this equation by cross-multiplying and rearranging gives:
T2 = (145 kPa x 362 K) / 123 kPa
T2 = 424.6 K
Finally, we can convert the temperature from Kelvin to Celsius by subtracting 273.15:
T2 = 424.6 K - 273.15
T2 = 151.45°C
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5. How many atoms are found in a 15.5 g sample of bismuth (Bi)? See periodic
table for the molar mass of bismuth. Use dimensional analysis, show all work to
receive full credit. (5 pts)
a. 9.33 × 1024 atoms
b.
3.24 × 10³ atoms
1.26 x 1022 atoms
d. 4.46 × 1022 atoms
C.
in the case of anionic polymerization using organometallic initiator, abby was able to get polystyrene with a number average molecular weight of 31,200 g/mole. please estimate the outcome of the new polymer if she double the initial monomer concentration and quadruple the initiator concentration from the original settings with all the other conditions/parameters and conversion being the same?
If Abby doubles the initial monomer concentration and quadruples the initiator concentration from the original settings, the outcome of the new polymer will likely have a higher number average molecular weight.
Abby's outcome of the new polymer will likely have a higher number average molecular weight because increasing the monomer concentration will lead to more monomer units being available for polymerization, while increasing the initiator concentration will lead to more initiation events, resulting in a higher degree of polymerization.
However, the exact molecular weight of the new polymer will depend on the efficiency of the polymerization reaction and any potential side reactions or termination events that may occur. It is possible that increasing the initiator concentration could also lead to more side reactions, such as chain transfer or termination, which could affect the final molecular weight distribution.
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A 74.28-g sample of Ba(OH) is dissolved in enough water fo make 2.450 liters of solution. How
627871
many mL of this solution must be diluted with water in order to make 1.000 L of 0.100 M Ba(OH)?
565 mL of this solution must be diluted with water in order to make 1.000 L of 0.100 M [tex](Ba(OH) _{2} )[/tex].
Mass of [tex](Ba(OH) _{2} )[/tex] = 72.28 g
Volume of solution = 2.450 L
Molarity of water = 0.1 mole/L
Volume of water = 1000 L
To begin with, we must count the moles of Ba (OH)2 in the original solution:
[tex]n(Ba(OH) _{2} )[/tex] = 171.34g/mol/74.28g
=0.4335mol
0.100 moles of [tex](Ba(OH) _{2} )[/tex] are needed to make 1.000 L of a 0.100M [tex](Ba(OH) _{2} )[/tex] solution.
As a result, the starting solution's volume that has to be diluted is equal to:
V=2.450L× 0.4335mol/0.100mol
=0.565L
0.565*1000ml
=565mL
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Complete question:
A 74.28-g sample of Ba (OH)2 is dissolved in enough water to make 2.450 liters of solution. How many mL of this solution must be diluted with water in order to make 1.000 L of 0.100 M Ba(OH)2?
The compound nickel(II) sulfate is a strong electrolyte. Write the reaction when solid nickel(II) sulfate is put into water.
Include states of matter.
When solid nickel(II) sulfate (NiSO4) is put into water, it dissociates completely into its constituent ions. The chemical equation for this process can be written as:
NiSO4(s) → Ni2+(aq) + SO42-(aq)
In this equation, (s) represents the solid state, while (aq) represents the aqueous state, which indicates that the ions are dissolved in water.
Nickel(II) sulfate is a soluble salt that dissociates readily in water, meaning that it is a strong electrolyte. This property allows it to conduct electricity when dissolved in water and is often used in various industrial and laboratory applications, including electroplating, catalysts, and batteries.
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How can you differentiate Hydrogen and carbon dioxide gases. (by flame)
The presence of hydrogen would be indicated by a pale blue flame that is nearly invisible in broad daylight, but the presence of carbon dioxide would be indicated by the flame going out.
Why do carbon dioxide and hydrogen gas flames differ from one another?A flame ignited by hydrogen gas emits a barely perceptible pale blue flame under normal lighting conditions. This is due to the flame that hydrogen gas produces mostly emitting light in the ultraviolet spectrum, which is invisible to the human eye.
On the other side, a flame is put out when carbon dioxide gas is added to it. This is because carbon dioxide is a gas that does not support burning and is not flammable.
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Theo watches the Moon every night for four weeks. He notices that
Theo watches the Moon every night for four weeks, he notices that how the Moon's position in the sky changes over time.
What does Theo notice ?Here are some things that Theo might observe or learn about the Moon:
The Moon's phases: By watching the Moon every night for four weeks, Theo would likely observe the changing phases of the Moon as it orbits the Earth. The Moon goes through a complete cycle of phases roughly once a month, which includes the new moon, waxing crescent, first quarter, waxing gibbous, full moon, waning gibbous, third quarter, and waning crescent.
The Moon's position in the sky: Theo might also notice how the Moon's position in the sky changes over time. The Moon rises and sets at different times each night, and its position in the sky also changes depending on its phase and location relative to the horizon.
The Moon's motion: By observing the Moon's position in the sky each night, Theo might notice that the Moon appears to move relative to the stars.
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what is the ph of a solution where the ratio of the acidic form of serine to the basic form of serine is 60.0?
The ratio of the acidic form of serine to the basic form of serine can be expressed using the Henderson-Hasselbalch equation:
pH = pKa + log([A-]/[HA])
where pKa is the dissociation constant of serine (which is around 2.2), [A-] is the concentration of the basic form of serine, and [HA] is the concentration of the acidic form of serine.
Assuming that the total concentration of serine is 1.0 (i.e., [A-] + [HA] = 1.0), we can set up the following equation:
60 = [A-]/[HA]
or
[A-] = 60[HA]
Substituting this expression for [A-] into the Henderson-Hasselbalch equation, we get:
pH = 2.2 + log(60[HA]/[HA]) = 2.2 + log(60) = 4.8
Therefore, the pH of the solution where the ratio of the acidic form of serine to the basic form of serine is 60.0 is approximately 4.8.
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which does not describe radon-222? group of answer choices its effects can be reduced by increasing ventilation. it exists in the igneous rock granite all around the world. it binds with hemoglobin in the blood and can lead to death. it seeps into homes through cracks in the foundation or soil. it is a radioactive gas that occurs from the natural decay of uranium
The statement that does not describe radon-222 is It binds with hemoglobin in the blood and can lead to death.
Radon-222 is a radioactive gas that occurs from the natural decay of uranium. It exists in igneous rock granite all around the world and can seep into homes through cracks in the foundation or soil. Its effects can be reduced by increasing ventilation in the affected areas.
This statement is inaccurate because radon does not bind with hemoglobin in the blood. Instead, radon gas decays into radioactive particles that can be inhaled and damage lung tissue, increasing the risk of lung cancer.
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Need help please!! Don’t know any of this.
1. The mass (in grams) of FeBr₃ produced from 65 g of Br₂ is 80.13 g
2. The mole of CO₂ formed from 10 moles of C₅H₁₂ is 50 moles
3. The moles of MnCl₂ prepared from 52.1 grams of MnO₂ is 0.6 mole
1. How do i determine the mass of FeBr₃ produced?The mass of FeBr₃ produced can be obtained as illustrated below:
2Fe + 3Br₂ -> 2FeBr₃
Molar mass of Br₂ = 160 g/molMass of Br₂ from the balanced equation = 3 × 160 = 480 g Molar mass of FeBr₃ = 295.85 g/molMass of FeBr₃ from the balanced equation = 2 × 295.85 = 591.7 gFrom the balanced equation above,
480 g of Br₂ reacted to produce 591.7 g of FeBr₃
Therefore,
65 g of Br₂ will react to produce = (65 × 591.7) / 480 = 80.13 g of FeBr₃
Thus, the mass of FeBr₃ produced is 80.13 g
2. How do i determine the mole of CO₂ formed?The mole of CO₂ formed can be obtained as follow:
C₅H₁₂ + 8O₂ -> 5CO₂ + 6H₂O
From the balanced equation above,
1 mole of C₅H₁₂ reacted to produce 5 moles of CO₂
Therefore,
10 moles of C₅H₁₂ will react to produce = 10 × 5 = 50 moles of CO₂
Thus, the mole of CO₂ formed is 50 moles
3. How do i determine the mole of MnCl₂ prepared?First, we shall obtain the mole of 52.1 g of MnO₂, Details below:
Mass of MnO₂ = 52.1 grams Molar mass of MnO₂ = 86.94 g/mol Mole of MnO₂ =?Mole = mass / molar mass
Mole of MnO₂ = 52.1 / 86.94
Mole of MnO₂ = 0.6 mole
Finally, we shall determine the mole of MnCl₂ prepared can be obtained as follow:
MnO₂ + 4HCl -> MnCl₂ + Cl₂ + 2H₂O
From the balanced equation above,
1 mole of MnO₂ reacted to produce 1 mole of MnCl₂
Therefore,
0.6 mole of MnO₂ will also react to produce 0.6 mole of MnCl₂
Thus, the mole of MnCl₂ prepared is 0.6 mole
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Calculate AH for the reaction:
C2H4 (g) + 3O2 (g)--> 2H2O (g) + 2CO2 (g)
The enthalpy change or AH for the reaction is -1560.9 kJ/mol. This negative value indicates that the reaction is exothermic, meaning it releases energy in the form of heat to the surroundings.
To calculate the enthalpy change (ΔH) or AH for the reaction:C2H4 (g) + 3O2 (g) → 2H2O (g) + 2CO2 (g)
We can use the standard enthalpies of formation (∆Hf°) of the products and reactants to determine the overall enthalpy change. The ∆Hf° values can be found in a reference table or online database.
The balanced equation tells us that 1 mole of C2H4 reacts with 3 moles of O2 to form 2 moles of H2O and 2 moles of CO2. So, we can write:
ΔH° = [2∆Hf°(H2O) + 2∆Hf°(CO2)] - [∆Hf°(C2H4) + 3∆Hf°(O2)]
Substituting the ∆Hf° values for each substance, we get:
ΔH° = [2(-241.8 kJ/mol) + 2(-393.5 kJ/mol)] - [(52.3 kJ/mol) + 3(0 kJ/mol)] ΔH° = -1560.9 kJ/mol
Therefore, the enthalpy change or AH for the reaction is -1560.9 kJ/mol. This negative value indicates that the reaction is exothermic, meaning it releases energy in the form of heat to the surroundings.
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write the net ionic equation for the acid-base hydrolysis equilibrium that is established when ammonium nitrate is dissolved in water. (use h3o instead of h .)
The net ionic equation for the acid-base hydrolysis equilibrium that is established when ammonium nitrate is dissolved in water is given below:Answer: NH4+(aq) + H2O(l) ⇌ H3O+(aq) + NH3(aq) + NO3-(aq).
The ionic equation is a chemical equation in which the electrolytes in aqueous solution are represented by their actual ions rather than their complete formulas. It indicates that ions undergo a chemical reaction to produce a new compound.
The net ionic equation displays the actual chemical reaction taking place in an aqueous solution. It is derived by eliminating spectator ions, which do not play any active role in the chemical reaction.The acid-base hydrolysis equilibrium is as follows:NH4+(aq) + H2O(l) ⇌ NH3(aq) + H3O+(aq).
The ammonium ion hydrolyzes to form ammonium ion and hydronium ions. The nitrate ion is a spectator ion that does not participate in the reaction. Therefore, the net ionic equation is given by:NH4+(aq) + H2O(l) ⇌ H3O+(aq) + NH3(aq).
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what is the difference between endothermic and exothermic process in chemistry
Answer:)
In simple terms, the endothermic reactions
absorb energy from the surrounding that is
in the form of heat. On the other hand, an
exothermic reaction releases energy into the
surrounding of the system.
Under a pressure of 862 kPa, a gas has a volume of 752 cm^3. The pressure is increased, without changing the temperature, until the volume is 624 cm^3. What is the new pressure?
Boyle's Law states that a gas's pressure and volume are inversely related at a given temperature. Therefore, P1V1 = P2V2. The new pressure is 1037.05 kPa as a result.
What is the pressure of a gas with a 725 ml volume?The pressure of a gas with a volume of 725 mL and a pressure of 0.970 atm is allowed to increase while maintaining a constant temperature.
To determine the new pressure, we can plug in the indicated values:
P1 = 862 kPa, V1 = 752 cm³, V2 = 624 cm³
P1V1 = P2V2
862 kPa x 752 cm³ = P2 x 624 cm³
647024 = 624P2
P2 = 647024/624
P2 = 1037.05 kPa
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how many atoms is in Ni(C2H3O2)4
Answer:
there are 37 atoms
Explanation:
The formula for nickel(II) acetate tetrahydrate is Ni(C2H3O2)4. To calculate the number of atoms in the formula, we need to count the number of atoms of each element and then multiply each by the number of times it appears in the formula.
Ni: There is 1 Ni atom in the formula.
C: There are 8 C atoms (4 from each C2H3O2) in the formula.
H: There are 12 H atoms (3 from each C2H3O2) in the formula.
O: There are 16 O atoms (4 from each C2H3O2) in the formula.
Therefore, the total number of atoms in the formula is 1 + 8 + 12 + 16 = 37.
So there are 37 atoms in Ni(C2H3O2)4.
of the encircled carbonyl groups in the compound below, how many of these groups could undergo reduction with sodium borohydride?
The part 2 in the attached image will undergo reduction with sodium borohydride.
Sodium borohydride (NaBH₄) is a commonly used reducing agent in organic chemistry. It is primarily used to reduce carbonyl groups (aldehydes and ketones) to their corresponding alcohols. Sodium borohydride can also reduce some other functional groups, such as imines and acid chlorides, but its reactivity towards these groups is much lower compared to carbonyls.
In general, the carbonyl groups in a molecule are the most likely functional groups to undergo reduction with sodium borohydride. Other functional groups such as alkenes, alkynes, aromatic rings, and alcohols are generally unreactive towards sodium borohydride.
Therefore, if your compound contains any carbonyl groups (such as aldehydes or ketones), those groups would be the most likely candidates for reduction with sodium borohydride. Part 2 is a carbonyl group, hence it will react.
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b) explain the meaning of the term ld50 (ed50). what is the ld50 concentration of cuso4 for brine shrimp?
The LD50 concentration of CuSO₄ for brine shrimp is reported to be around 2.75 ppm (parts per million), which means that if 50% of the brine shrimp population were exposed to this concentration of CuSO₄, they would die as a result of the exposure
The LD50 and ED50 are both terms commonly used in toxicology to express the effectiveness or toxicity of a substance.
The LD50, which stands for "lethal dose 50," is the amount of a substance required to cause death in 50% of the test population. It is typically expressed in units of milligrams or micrograms of the substance per kilogram of body weight of the test animal.
On the other hand, the ED50 stands for "effective dose 50," which is the amount of a substance required to produce a desired effect in 50% of the test population. It is commonly used in pharmacology to measure the potency of a drug.
In the case of the brine shrimp, the LD50 concentration of CuSO4 (copper sulfate) would be the amount of CuSO4 that would cause the death of 50% of the shrimp population in a given test. It is important to note that the LD50 can vary depending on various factors such as the species being tested, the method of exposure, and the duration of exposure.
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a salt bridge . a. is made up of an aqueous ionic compound b. has positive ions that are attracted to the cathode c. has negative ions that are attracted to the anode d. allows the reaction of the galvanic cell to continue e. all of the above
The correct answer is: "e. all of the above." A salt bridge is an essential component of a galvanic cell. It is made up of an aqueous ionic compound that allows the reaction of the galvanic cell to continue.
The salt bridge contains positive ions that are attracted to the cathode and negative ions that are attracted to the anode.
By allowing ions to flow between the two half-cells of the galvanic cell, the salt bridge prevents the buildup of charge that could halt the reaction.
This ensures that the cell can continue to produce electrical energy until the reactants are fully consumed.
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What is the Molarity of a 6.3 L dilution of a 0.99Molar solution 3.4 L
Answer:
To solve this problem, we can use the dilution formula: M1V1 = M2V2 Where M1 is the initial molarity, V1 is the initial volume, M2 is the final molarity, and V2 is the final volume. We are given that the initial molarity is 0.99M and the initial volume is 3.4 L. We can use this information to find M2: M1V1 = M2V2 (0.99M)(3.4 L) = M2(6.3 L) M2 = (0.99M)(3.4 L) / (6.3 L) M2 = 0.5357 M Therefore, the molarity of a 6.3 L dilution of a 0.99M solution with an initial volume of
Answer:
0.534 M.
Explanation:
Molarity is a measure of the concentration of a solution, defined as the number of moles of solute per liter of solution. When a solution is diluted by adding more solvent, the number of moles of solute remains the same, but the volume of the solution increases, resulting in lower molarity.
In this case, you have a 3.4 L solution with a molarity of 0.99 M. This means that the number of moles of solute in this solution is 3.4 L * 0.99 mol/L = 3.366 moles.
If you dilute this solution to a final volume of 6.3 L by adding more solvent, the number of moles of solute remains the same (3.366 moles), but the volume has increased to 6.3 L. So the molarity of the diluted solution is 3.366 moles / 6.3 L = 0.534 M.
A scientist wants to perform a reaction in a vacuum chamber to control the experiment as much as possible and to prevent other variables from impacting the reaction. The scientist is trying to determine if the reaction is endothermic or exothermic and measure how much energy is absorbed or given off. Is this a valid approach? Why or why not? In three to five sentences, explain your reasoning.
Performing a reaction in a vacuum chamber to control the experiment is a valid approach to prevent external variables from impacting the reaction.
However, it may not be sufficient to determine if the reaction is endothermic or exothermic and measure the amount of energy absorbed or given off. This is because the vacuum chamber only isolates the reaction from the environment, but it does not provide a way to measure the energy changes that occur during the reaction. To measure the energy changes, the scientist should use techniques such as calorimetry, which directly measures the heat absorbed or released by the reaction.
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What is the molar mass of an unknown if a 0.45 M solution is created by dissolving 12 grams in 425 mL of water?
To calculate the molar mass of the unknown substance, we need to use the formula:
Molar mass = (mass of solute) / (number of moles of solute)
First, let's calculate the number of moles of solute in the solution:
Number of moles = (concentration) x (volume in liters)
We know that the concentration of the solution is 0.45 M, and the volume of the solution is 425 mL, which is equivalent to 0.425 L. Substituting these values into the formula, we get:
Number of moles = 0.45 M x 0.425 L
Number of moles = 0.19125 moles
Next, we can calculate the mass of the solute (the unknown substance) by using the formula:
mass = number of moles x molar mass
Rearranging the formula, we get:
molar mass = mass / number of moles
We know that the mass of the solute is 12 grams, and we have already calculated the number of moles as 0.19125 moles. Substituting these values into the formula, we get:
molar mass = 12 g / 0.19125 moles
molar mass = 62.8 g/mol
Therefore, the molar mass of the unknown substance is 62.8 g/mol.
if there is no diethyl ether in the lab, what other solvent can you use as an alternative? select one: methanol ethyl acetate tetrahydrofuran water
While considering a good solvent alternative for diethyl ether, the best one will be ethyl acetate. It can be used for extraction due to its polarity and less toxicity.
Diethyl ether is one of the commonly used solvent in extraction process of non-polar or slightly polar organic compounds. This is because it does not have hydrogen bonding. So here methanol cannot be used as it has extensive hydrogen bonding and non-polar compounds might not dissolve.
Water also cannot be used because of its polar nature. So organic compounds does not dissolve. Tetrahydrofuran can be used as a solvent, but toxicity levels are higher compared to diethyl ether.
So the alternative that can be used is ethyl acetate, which is also widely used solvent in extraction of non-polar compounds. Also it has less toxicity compared to THF.
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The diagram shows part of a DNA molecule. Using the order of bases in the top strand, write the letters of the bases that belong on the bottom strand.
Answer:
G, A, A, T, C, C, G, A, A, T, G, G, T
Explanation:
. consider a buffer solution that contains a mixture of aqueous hcn and kcn. a. write the net ionic equation for the reaction that occurs when a few drops of hcl are added to the solution. b. write the net ionic equation for the reaction that occurs when a few drops of naoh are added to the solution
The ionic equations are as follows:
[tex]H^{+} (aq) + CN^{-} (aq) < -- > HCN(aq)[/tex]
[tex]CN^{-} (aq) + H2O (l) < = > HCN (aq) + OH^{-} (aq)[/tex]
The buffer solution containing a mixture of aqueous HCN and KCN can be represented as:
[tex]HCN(aq) + CN^{-} (aq) + K^{+} (aq) < --- > HCN(aq) + KCN(aq)[/tex]
a. When a few drops of HCl are added to the buffer solution, the H+ ions from the HCl react with the CN- ions in the buffer solution to form HCN. The net ionic equation for the reaction is:
[tex]H^{+} (aq) + CN^{-} (aq) < -- > HCN(aq)[/tex]
b. When a few drops of NaOH are added to the buffer solution, the OH- ions from the NaOH react with the HCN molecules in the buffer solution to form CN- ions. The net ionic equation for the reaction is:
[tex]CN^{-} (aq) + H2O (l) < = > HCN (aq) + OH^{-} (aq)[/tex]
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tech a states that overheated catalysts cannot be restored and must be replaced. tech b states that overheated catalysts can be easily restored by driving the vehicle for an extended time under a moderate load. who is correct?
Tech A is correct who says that overheated catalysts cannot be restored and must be replaced.
In chemistry, a catalyst is any substance that speeds up a reaction without consuming itself. Many crucial biochemical reactions are catalysed by enzymes, which are substances that occur naturally.
The majority of solid catalysts are made of metals, or the oxides, sulphides, and halides of metals, as well as of the semimetallic elements silicon, aluminium, and boron. Solid catalysts are frequently dispersed in materials known as catalyst supports, while gaseous and liquid catalysts are typically used in their pure form or in combination with appropriate carriers or solvents.
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which of the following gives the definition of ion-dipole attraction? select the correct answer below: ion-dipole attraction is attraction between an ion and the polar bond(s) in a nonpolar molecule. ion-dipole attraction is a physical process accompanying the dissolution of an ionic compound in which the compound's constituent ions are solvated and dispersed throughout the solution. ion-dipole attraction is the scattering of visible light by a solution. ion-dipole attraction is the electrostatic attraction between an ion and a polar molecule.
Ion-dipole attraction is the electrostatic attraction between an ion and a polar molecule. The correct answer is d.
Ion-dipole attraction is an intermolecular force that arises from the electrostatic attraction between an ion and a polar molecule. The ion is attracted to the partial charges on the polar molecule due to the separation of positive and negative charges within the molecule. This attraction is important in a variety of chemical processes, including dissolution of ionic compounds in solvents, such as water, where the solvent molecules surround and solvate the ions.
Ion-dipole interactions also play a significant role in many biological processes, such as protein folding and enzyme catalysis, as well as in industrial processes, such as separating ions in solution through methods like ion-exchange chromatography. Hence, the correct answer is d.
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if the coefficients in the redox reaction are doubled, how will the given quantities be affected for a voltaic cell under nonstandard conditions?
When the coefficients in the redox reaction are doubled, the given quantities will be affected for a voltaic cell under nonstandard conditions in the following ways.
Explanation:
An increase in the coefficients of a balanced redox reaction increases the number of moles of the reacting species. Thus, an increase in the coefficients of a redox reaction would result in an increase in the cell potential.
Furthermore, the reaction quotient Q would become smaller due to an increase in the concentrations of products and a decrease in the concentrations of reactants. This shift toward the products would make the reaction more spontaneous.The increase in coefficients would result in an increase in the molar quantities of each species, resulting in a change in the Q value. The standard EMF of the cell is unaffected since it is based solely on standard conditions. The value of ΔG, which is directly related to the potential difference in a galvanic cell, changes as the value of Q changes.
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