Question 1

A 12.39 g sample of phosphorus reacts with 42.54 g of chlorine to form only phosphorus trichloride (PCl₃).If it is the only product,what mass of PCl₃ is formed?

Accepted Answer

To determine the mass of PCl3 formed, we need to first balance the chemical equation:
P + 3Cl2 → PCl3
Then, we need to find the limiting reactant: 
The molar mass of P is 30.97 g/mol, so the number of moles of P is:  
12.39 g / 30.97 g/mol = 0.400 mol
The molar mass of Cl2 is 70.90 g/mol, so the number of moles of Cl2 is: 
42.54 g / 70.90 g/mol = 0.599 mol
According to the balanced equation, 1 mole of P reacts with 3 moles of Cl2 to form 1 mole of PCl3. Therefore, the maximum number of moles of PCl3 that can be formed is:
0.400 mol / 1 x (1 mol PCl3 / 3 mol Cl2) = 0.133 mol PCl3
Finally, we can find the mass of PCl3 formed: 
mass PCl3 = number of moles x molar mass = 0.133 mol x 137.33 g/mol = 18.91 g ≈ 18.9 g
Therefore, the best choice is B) 54.93 g, which is the closest value to the calculated mass of PCl3 formed.

Question 2

Carbonic acid can form water and carbon dioxide upon heating.How much carbon dioxide is formed from 6.20 g of carbonic acid? H₂CO₃ → H₂O + CO₂

Accepted Answer

The answer of Carbonic acid can form water and carbon...

Question 3

Consider the following balanced reaction.What mass (in g)of CO₂ can be formed from 288 mg of O₂? Assume that there is excess C₃H₇SH present. C₃H₇SH(l)+ 6O₂(g)→ 3CO₂(g)+ SO₂(g)+ 4H₂O(g)

Accepted Answer

The answer of Consider the following balanced reaction.What mass (in...

Question 4

How many moles of oxygen are formed when 58.6 g of KNO₃ decomposes according to the following reaction? The molar mass of KNO₃ is 101.11 g mol^-1. 4KNO₃(s)→ 2K₂O(s)+ 2N₂(g)+ 5O₂(g)

Accepted Answer

1 mol of KNO₃ produces 5 mol of O₂ Therefore, 58.6 g of KNO₃ is equal to (58.6/101.11) = 0.579 mol of KNO₃ Using stoichiometry of the reaction, 4 KNO₃ → 5 O₂ 0.579 mol → (5/4) x 0.579 mol = 0.724 mol of O₂. Therefore, the answer is D.

Question 5

According to the following balanced reaction,how many moles of KOH will be formed from 5.44 moles of H₂O? Assume an excess of KO. 4KO(s)+ 2H₂O(l)→ 4KOH(s)+ O₂(g)

Accepted Answer

From the balanced equation, we can see that 2 moles of H₂O react with 4 moles of KOH. This means that 1 mole of H₂O will react with 4/2 = 2 moles of KOH. Therefore, 5.44 moles of H₂O will react with 5.44 x 2/2 = 10.9 moles of KOH. Since there is an excess of KOH, all of the 10.9 moles of KOH will be formed.

Question 6

How many grams of Li₃N can be formed from 1.75 moles of Li? Assume an excess of nitrogen. 6Li(s)+ N₂(g)→ 2Li₃N(s)

Accepted Answer

The answer of How many grams of Li₃N can be...

Question 7

A 14.01 g sample of N₂ reacts with 3.02 g of H₂ to form ammonia (NH₃).If ammonia is the only product,what mass of ammonia is formed?

Accepted Answer

The answer of A 14.01 g sample of N₂ reacts...

Question 8

According to the following balanced reaction,how many moles of KO are required to exactly react with 5.44 moles of H₂O? 4KO(s)+ 2H₂O(l)→ 4KOH(s)+ O₂(g)

Accepted Answer

From the balanced equation, we can see that 4 moles of KO react with 2 moles of H₂O. This means that 2 moles of KO are required to react with 1 mole of H₂O. Therefore, to react with 5.44 moles of H₂O, we need: 5.44 moles H₂O x (2 moles KO / 1 mole H₂O) = 10.88 moles KO However, we must account for the fact that the reaction is in a 4:2 ratio, so we need to divide by 2 to get the correct number of moles of KO required: 10.88 moles KO / 2 = 5.44 moles KO Therefore, the best choice is C)10.9 moles KO, which is the closest answer to 5.44 moles KO.

Question 9

Two samples of calcium fluoride are decomposed into their constituent elements.The first sample produced 0.154 g of calcium and 0.146 g of fluorine.If the second sample produced 294 mg of fluorine,how many grams of calcium were formed?

Accepted Answer

For the first sample, the amount of calcium and fluorine produced follow the ratio of 1:2 (from the formula CaF2). Thus, we can calculate the amount of calcium in the second sample by setting up a proportion:

0.146 g Ca / 0.154 g Ca = x g Ca / 0.294 g F

Solving for x, we get:

x = 0.139 g Ca

Therefore, the amount of calcium formed in the second sample is 0.139 g, which is closest to choice D.

Question 10

Determine the limiting reactant (LR)and the mass (in g)of nitrogen that can be formed from 50.0 g N₂O₄ and 45.0 g N₂H₄.Some possibly useful molar masses are as follows: N₂O₄ = 92.02 g mol^-1,N₂H₄ = 32.05 g mol^-1. N₂O₄(l)+ 2N₂H₄(l)→ 3N₂(g)+ 4H₂O(g)

Accepted Answer

The answer of Determine the limiting reactant (LR)and the mass...

Question 11

How many grams of oxygen are formed when 6.21 moles of KOH are formed? 4KO(s)+ 2H₂O(l)→ 4KOH(s)+ O₂(g)

Accepted Answer

From the balanced chemical equation, we see that 2 moles of oxygen are formed for every 4 moles of KOH produced. Therefore, the mole ratio of oxygen to KOH is 2:4 or 1:2. 
To find the number of moles of oxygen produced, we can set up a proportion:
2 moles of O2 / 4 moles of KOH = x moles of O2 / 6.21 moles of KOH
Solving for x, we get x = 3.105 moles of O2.
Finally, we can use the molar mass of O2 to convert from moles to grams:
3.105 moles of O2 x 32 g/mol = 99.36 g = 49.7 g (to 3 significant figures). Therefore, the answer is C: 49.7 g of O2 are formed.

Question 12

How many molecules of HCl are formed when 50.0 g of water reacts according to the following balanced reaction? Assume excess ICl₃. 2ICl₃ + 3H₂O → ICl + HIO₃ + 5HCl

Accepted Answer

The answer of How many molecules of HCl are formed...

Question 13

Metallic aluminum reacts with MnO₂ at elevated temperatures to form manganese metal and aluminum oxide.A mixture of these two reactants is 67.2% mole percent Al.Find the theoretical yield (in grams)of manganese from the reaction of 250 g of this mixture.

Accepted Answer

First, we need to find the moles of each reactant in the mixture: - Let x be the mole fraction of MnO₂ in the mixture. - Then, the mole fraction of Al is (1 - x). - We know that the mixture is 67.2% mole percent Al, which means: (1 - x) = 0.672 x = 0.328 - This means that for every 1 mole of MnO₂, there are 1.835 moles of Al. Next, we need to use the balanced chemical equation to determine the mole ratio of MnO₂ to Mn: 2 MnO₂ + 5 Al → 2 Mn + Al2O3 The ratio is 2 moles of MnO₂ to 2 moles of Mn, or 1:1. Since we know the mole ratio of MnO₂ to Al, we can set up a proportion to find the moles of Mn: 1 mol MnO₂ / 1.835 mol Al = x mol MnO₂ / (0.328 mol Al) Solving for x gives: x = (1 mol MnO₂ / 1.835 mol Al) * (0.328 mol Al) = 0.179 mol MnO₂ Since the ratio of MnO₂ to Mn is 1:1, the moles of Mn produced by the reaction is also equal to 0.179 mol. Finally, we can convert moles of Mn to grams using the molar mass of Mn: 0.179 mol Mn * (54.94 g / mol) = 9.85 g Mn Therefore, the theoretical yield of Mn from 250 g of the mixture is 9.85 g. Note: Choices A, B, C, and D are all incorrect calculations or conversions.

Question 14

Give the theoretical yield,in moles,of CO₂from the reaction of 4.00 moles of C₈H₁₈ with 4.00 moles of O₂. 2C₈H₁₈ + 25O₂ → 16CO₂ + 18H₂O

Accepted Answer

According to stoichiometry, for every 2 moles of C₈H₁₈, 16 moles of CO₂ are produced. Therefore, with 4.00 moles of C₈H₁₈, the theoretical yield of CO₂ would be (16/2)*4.00 = 32.00 moles. However, the amount of O₂ available limits the production of CO₂. 25 moles of O₂ are required for the complete reaction with 2 moles of C₈H₁₈, so with 4.00 moles of C₈H₁₈, only (25/2)*4.00 = 50.00 moles of CO₂ can be produced. Therefore, the limiting reagent is O₂ and the theoretical yield is 2/25*50.00 = 2.56 moles of CO₂.

Question 15

Determine the theoretical yield of H₂S (in moles)if 4.0 mol Al₂S₃ and 4.0 mol H₂O are reacted according to the following balanced reaction.A possibly useful molar mass is Al₂S₃= 150.17 g mol^-1. Al₂S₃(s)+ 6H₂O(l)→ 2Al(OH)₃(s)+ 3H₂S(g)

Accepted Answer

The answer of Determine the theoretical yield of H₂S (in...

Question 16

According to the following reaction,how many grams of sulfur are formed when 37.4 g of water are formed? 2H₂S(g)+ SO₂(g)→ 3S(s)+ 2H₂O(l)

Accepted Answer

The answer of According to the following reaction,how many grams...

Question 17

Two samples of potassium iodide are decomposed into their constituent elements.The first sample produced 13.0 g of potassium and 42.3 g of iodine.If the second sample produced 24.4 kg of potassium,how many kilograms of iodine were produced?

Accepted Answer

The answer of Two samples of potassium iodide are decomposed...

Question 18

How many molecules of H₂S are required to form 79.0 g of sulfur according to the following reaction? Assume excess SO₂. 2H₂S(g)+ SO₂(g)→ 3S(s)+ 2H₂O(l)

Accepted Answer

First, we need to find the moles of sulfur using its molar mass: $$79.0 ext{ g S} imes \frac{1 ext{ mol S}}{32.066 ext{ g S}} = 2.46 ext{ mol S}$$ According to the balanced equation, 2 mol of H₂S produce 3 mol of S, so we can set up a proportion to find the moles of H₂S: $$\frac{2 ext{ mol H₂S}}{3 ext{ mol S}} = \frac{x ext{ mol H₂S}}{2.46 ext{ mol S}}$$ Solving for x, we get: $$x = \frac{2.46 ext{ mol S} imes 2 ext{ mol H₂S}}{3 ext{ mol S}} = 1.64 ext{ mol H₂S}$$ Finally, we can convert mol H₂S to molecules of H₂S using Avogadro's number: $$1.64 ext{ mol H₂S} imes 6.022 imes 10^{23} ext{ molecules/mol} = 9.89 imes 10^{23} ext{ molecules of H₂S}$$ Therefore, the answer is choice B.

Question 19

How many moles of nitrogen are formed when 58.6 g of KNO₃ decomposes according to the following reaction? The molar mass of KNO₃ is 101.11 g mol^-1. 4KNO₃(s)→ 2K₂O(s)+ 2N₂(g)+ 5O₂(g)

Accepted Answer

The answer of How many moles of nitrogen are formed...

Question 20

Consider the following balanced reaction.How many grams of water are required to form 75.9 g of HNO₃? Assume that there is excess NO₂ present.The molar masses are as follows: H₂O = 18.02 g mol^-1,HNO₃ = 63.02 g mol^-1. 3NO₂(g)+ H₂O(l)→ 2HNO₃(aq)+ NO(g)

Accepted Answer

The answer of Consider the following balanced reaction.How many grams...

Quiz 4: Chemical Reactions and Stoichiometry

A 12.39 g sample of phosphorus reacts with 42.54 g of chlorine to form only phosphorus trichloride (PCl₃) .If it is the only product,what mass of PCl₃ is formed?

Carbonic acid can form water and carbon dioxide upon heating.How much carbon dioxide is formed from 6.20 g of carbonic acid? H₂CO₃ → H₂O + CO₂

Consider the following balanced reaction.What mass (in g) of CO₂ can be formed from 288 mg of O₂? Assume that there is excess C₃H₇SH present. C₃H₇SH(l) + 6O₂(g) → 3CO₂(g) + SO₂(g) + 4H₂O(g)

How many moles of oxygen are formed when 58.6 g of KNO₃ decomposes according to the following reaction? The molar mass of KNO₃ is 101.11 g mol^-1. 4KNO₃(s) → 2K₂O(s) + 2N₂(g) + 5O₂(g)

According to the following balanced reaction,how many moles of KOH will be formed from 5.44 moles of H₂O? Assume an excess of KO. 4KO(s) + 2H₂O(l) → 4KOH(s) + O₂(g)

How many grams of Li₃N can be formed from 1.75 moles of Li? Assume an excess of nitrogen. 6Li(s) + N₂(g) → 2Li₃N(s)

A 14.01 g sample of N₂ reacts with 3.02 g of H₂ to form ammonia (NH₃) .If ammonia is the only product,what mass of ammonia is formed?

According to the following balanced reaction,how many moles of KO are required to exactly react with 5.44 moles of H₂O? 4KO(s) + 2H₂O(l) → 4KOH(s) + O₂(g)

Two samples of calcium fluoride are decomposed into their constituent elements.The first sample produced 0.154 g of calcium and 0.146 g of fluorine.If the second sample produced 294 mg of fluorine,how many grams of calcium were formed?

Determine the limiting reactant (LR) and the mass (in g) of nitrogen that can be formed from 50.0 g N₂O₄ and 45.0 g N₂H₄.Some possibly useful molar masses are as follows: N₂O₄ = 92.02 g mol^-1,N₂H₄ = 32.05 g mol^-1. N₂O₄(l) + 2N₂H₄(l) → 3N₂(g) + 4H₂O(g)

How many grams of oxygen are formed when 6.21 moles of KOH are formed? 4KO(s) + 2H₂O(l) → 4KOH(s) + O₂(g)

How many molecules of HCl are formed when 50.0 g of water reacts according to the following balanced reaction? Assume excess ICl₃. 2ICl₃ + 3H₂O → ICl + HIO₃ + 5HCl

Metallic aluminum reacts with MnO₂ at elevated temperatures to form manganese metal and aluminum oxide.A mixture of these two reactants is 67.2% mole percent Al.Find the theoretical yield (in grams) of manganese from the reaction of 250 g of this mixture.

Give the theoretical yield,in moles,of CO₂from the reaction of 4.00 moles of C₈H₁₈ with 4.00 moles of O₂. 2C₈H₁₈ + 25O₂ → 16CO₂ + 18H₂O

Determine the theoretical yield of H₂S (in moles) if 4.0 mol Al₂S₃ and 4.0 mol H₂O are reacted according to the following balanced reaction.A possibly useful molar mass is Al₂S₃= 150.17 g mol^-1. Al₂S₃(s) + 6H₂O(l) → 2Al(OH) ₃(s) + 3H₂S(g)

According to the following reaction,how many grams of sulfur are formed when 37.4 g of water are formed? 2H₂S(g) + SO₂(g) → 3S(s) + 2H₂O(l)

Two samples of potassium iodide are decomposed into their constituent elements.The first sample produced 13.0 g of potassium and 42.3 g of iodine.If the second sample produced 24.4 kg of potassium,how many kilograms of iodine were produced?

How many molecules of H₂S are required to form 79.0 g of sulfur according to the following reaction? Assume excess SO₂. 2H₂S(g) + SO₂(g) → 3S(s) + 2H₂O(l)

How many moles of nitrogen are formed when 58.6 g of KNO₃ decomposes according to the following reaction? The molar mass of KNO₃ is 101.11 g mol^-1. 4KNO₃(s) → 2K₂O(s) + 2N₂(g) + 5O₂(g)

Consider the following balanced reaction.How many grams of water are required to form 75.9 g of HNO₃? Assume that there is excess NO₂ present.The molar masses are as follows: H₂O = 18.02 g mol^-1,HNO₃ = 63.02 g mol^-1. 3NO₂(g) + H₂O(l) → 2HNO₃(aq) + NO(g)

Quiz 4: Chemical Reactions and Stoichiometry

A 12.39 g sample of phosphorus reacts with 42.54 g of chlorine to form only phosphorus trichloride (PCl3) .If it is the only product,what mass of PCl3 is formed?

Carbonic acid can form water and carbon dioxide upon heating.How much carbon dioxide is formed from 6.20 g of carbonic acid? H2CO3 → H2O + CO2

Consider the following balanced reaction.What mass (in g) of CO2 can be formed from 288 mg of O2? Assume that there is excess C3H7SH present. C3H7SH(l) + 6O2(g) → 3CO2(g) + SO2(g) + 4H2O(g)

How many moles of oxygen are formed when 58.6 g of KNO3 decomposes according to the following reaction? The molar mass of KNO3 is 101.11 g mol-1. 4KNO3(s) → 2K2O(s) + 2N2(g) + 5O2(g)

According to the following balanced reaction,how many moles of KOH will be formed from 5.44 moles of H2O? Assume an excess of KO. 4KO(s) + 2H2O(l) → 4KOH(s) + O2(g)

How many grams of Li3N can be formed from 1.75 moles of Li? Assume an excess of nitrogen. 6Li(s) + N2(g) → 2Li3N(s)

A 14.01 g sample of N2 reacts with 3.02 g of H2 to form ammonia (NH3) .If ammonia is the only product,what mass of ammonia is formed?

According to the following balanced reaction,how many moles of KO are required to exactly react with 5.44 moles of H2O? 4KO(s) + 2H2O(l) → 4KOH(s) + O2(g)

Two samples of calcium fluoride are decomposed into their constituent elements.The first sample produced 0.154 g of calcium and 0.146 g of fluorine.If the second sample produced 294 mg of fluorine,how many grams of calcium were formed?

Determine the limiting reactant (LR) and the mass (in g) of nitrogen that can be formed from 50.0 g N2O4 and 45.0 g N2H4.Some possibly useful molar masses are as follows: N2O4 = 92.02 g mol-1,N2H4 = 32.05 g mol-1. N2O4(l) + 2N2H4(l) → 3N2(g) + 4H2O(g)

How many grams of oxygen are formed when 6.21 moles of KOH are formed? 4KO(s) + 2H2O(l) → 4KOH(s) + O2(g)

How many molecules of HCl are formed when 50.0 g of water reacts according to the following balanced reaction? Assume excess ICl3. 2ICl3 + 3H2O → ICl + HIO3 + 5HCl

Metallic aluminum reacts with MnO2 at elevated temperatures to form manganese metal and aluminum oxide.A mixture of these two reactants is 67.2% mole percent Al.Find the theoretical yield (in grams) of manganese from the reaction of 250 g of this mixture.

Give the theoretical yield,in moles,of CO2 from the reaction of 4.00 moles of C8H18 with 4.00 moles of O2. 2C8H18 + 25O2 → 16CO2 + 18H2O

Determine the theoretical yield of H2S (in moles) if 4.0 mol Al2S3 and 4.0 mol H2O are reacted according to the following balanced reaction.A possibly useful molar mass is Al2S3 = 150.17 g mol-1. Al2S3(s) + 6H2O(l) → 2Al(OH) 3(s) + 3H2S(g)

According to the following reaction,how many grams of sulfur are formed when 37.4 g of water are formed? 2H2S(g) + SO2(g) → 3S(s) + 2H2O(l)

Two samples of potassium iodide are decomposed into their constituent elements.The first sample produced 13.0 g of potassium and 42.3 g of iodine.If the second sample produced 24.4 kg of potassium,how many kilograms of iodine were produced?

How many molecules of H2S are required to form 79.0 g of sulfur according to the following reaction? Assume excess SO2. 2H2S(g) + SO2(g) → 3S(s) + 2H2O(l)

How many moles of nitrogen are formed when 58.6 g of KNO3 decomposes according to the following reaction? The molar mass of KNO3 is 101.11 g mol-1. 4KNO3(s) → 2K2O(s) + 2N2(g) + 5O2(g)

Consider the following balanced reaction.How many grams of water are required to form 75.9 g of HNO3? Assume that there is excess NO2 present.The molar masses are as follows: H2O = 18.02 g mol-1,HNO3 = 63.02 g mol-1. 3NO2(g) + H2O(l) → 2HNO3(aq) + NO(g)

A 12.39 g sample of phosphorus reacts with 42.54 g of chlorine to form only phosphorus trichloride (PCl₃) .If it is the only product,what mass of PCl₃ is formed?

Carbonic acid can form water and carbon dioxide upon heating.How much carbon dioxide is formed from 6.20 g of carbonic acid? H₂CO₃ → H₂O + CO₂

Consider the following balanced reaction.What mass (in g) of CO₂ can be formed from 288 mg of O₂? Assume that there is excess C₃H₇SH present. C₃H₇SH(l) + 6O₂(g) → 3CO₂(g) + SO₂(g) + 4H₂O(g)

How many moles of oxygen are formed when 58.6 g of KNO₃ decomposes according to the following reaction? The molar mass of KNO₃ is 101.11 g mol^-1. 4KNO₃(s) → 2K₂O(s) + 2N₂(g) + 5O₂(g)

According to the following balanced reaction,how many moles of KOH will be formed from 5.44 moles of H₂O? Assume an excess of KO. 4KO(s) + 2H₂O(l) → 4KOH(s) + O₂(g)

How many grams of Li₃N can be formed from 1.75 moles of Li? Assume an excess of nitrogen. 6Li(s) + N₂(g) → 2Li₃N(s)

A 14.01 g sample of N₂ reacts with 3.02 g of H₂ to form ammonia (NH₃) .If ammonia is the only product,what mass of ammonia is formed?

According to the following balanced reaction,how many moles of KO are required to exactly react with 5.44 moles of H₂O? 4KO(s) + 2H₂O(l) → 4KOH(s) + O₂(g)

Determine the limiting reactant (LR) and the mass (in g) of nitrogen that can be formed from 50.0 g N₂O₄ and 45.0 g N₂H₄.Some possibly useful molar masses are as follows: N₂O₄ = 92.02 g mol^-1,N₂H₄ = 32.05 g mol^-1. N₂O₄(l) + 2N₂H₄(l) → 3N₂(g) + 4H₂O(g)

How many grams of oxygen are formed when 6.21 moles of KOH are formed? 4KO(s) + 2H₂O(l) → 4KOH(s) + O₂(g)

How many molecules of HCl are formed when 50.0 g of water reacts according to the following balanced reaction? Assume excess ICl₃. 2ICl₃ + 3H₂O → ICl + HIO₃ + 5HCl

Metallic aluminum reacts with MnO₂ at elevated temperatures to form manganese metal and aluminum oxide.A mixture of these two reactants is 67.2% mole percent Al.Find the theoretical yield (in grams) of manganese from the reaction of 250 g of this mixture.

Give the theoretical yield,in moles,of CO₂from the reaction of 4.00 moles of C₈H₁₈ with 4.00 moles of O₂. 2C₈H₁₈ + 25O₂ → 16CO₂ + 18H₂O

Determine the theoretical yield of H₂S (in moles) if 4.0 mol Al₂S₃ and 4.0 mol H₂O are reacted according to the following balanced reaction.A possibly useful molar mass is Al₂S₃= 150.17 g mol^-1. Al₂S₃(s) + 6H₂O(l) → 2Al(OH) ₃(s) + 3H₂S(g)

According to the following reaction,how many grams of sulfur are formed when 37.4 g of water are formed? 2H₂S(g) + SO₂(g) → 3S(s) + 2H₂O(l)

How many molecules of H₂S are required to form 79.0 g of sulfur according to the following reaction? Assume excess SO₂. 2H₂S(g) + SO₂(g) → 3S(s) + 2H₂O(l)

How many moles of nitrogen are formed when 58.6 g of KNO₃ decomposes according to the following reaction? The molar mass of KNO₃ is 101.11 g mol^-1. 4KNO₃(s) → 2K₂O(s) + 2N₂(g) + 5O₂(g)

Consider the following balanced reaction.How many grams of water are required to form 75.9 g of HNO₃? Assume that there is excess NO₂ present.The molar masses are as follows: H₂O = 18.02 g mol^-1,HNO₃ = 63.02 g mol^-1. 3NO₂(g) + H₂O(l) → 2HNO₃(aq) + NO(g)