Question 1

When 11.0 g of calcium metal is reacted with water,5.00 g of calcium hydroxide is produced.Using the following balanced equation,calculate the percent yield for the reaction? Ca(s)+ 2 H₂O(l)→ Ca(OH)₂(aq)+ H₂(g)

Accepted Answer

First, we need to calculate the theoretical yield of calcium hydroxide:

Moles of Ca = 11.0 g / 40.08 g/mol = 0.274 mol
Moles of Ca(OH)2 = 0.274 mol / 1 = 0.274 mol (from the balanced equation)
Mass of Ca(OH)2 = 0.274 mol x 74.09 g/mol = 20.3 g

Now, we can calculate the percent yield:

Percent yield = (actual yield / theoretical yield) x 100%
Actual yield = 5.00 g

Percent yield = (5.00 g / 20.3 g) x 100% = 24.6%

Therefore, the best choice is B, with a percent yield of 24.6%.

Question 2

How many moles of BCl₃ are needed to produce 10.0 g of HCl(aq)in the following reaction? BCl₃(g)+ 3 H₂O(l)→ 3 HCl(aq)+ B(OH)₃(aq)

Accepted Answer

To solve the problem, we need to use stoichiometry and conversion of mass to moles. We know that the molar ratio of BCl₃ to HCl is 1:3. Therefore, we can set up a proportion: 10.0 g HCl × (1 mol HCl/36.46 g HCl) × (1 mol BCl₃/3 mol HCl) = 0.0914 mol BCl₃ The first conversion factor is from the molar mass of HCl, and the second conversion factor is from the balanced chemical equation. Therefore, the answer is A) 0.0914 mol.

Question 3

When silver nitrate reacts with barium chloride,silver chloride and barium nitrate are formed.How many grams of silver chloride are formed when 10.0 g of silver nitrate reacts with 15.0 g of barium chloride?

Accepted Answer

To solve this problem, we need to use stoichiometry and balance equations. 
The balanced chemical equation for the reaction between silver nitrate and barium chloride is: 
AgNO3 + BaCl2 -> AgCl + Ba(NO3)2

From the equation, we can see that 1 mole of silver nitrate reacts with 1 mole of barium chloride to produce 1 mole of silver chloride. 
First, we need to find the limiting reactant between the two given compounds. To do this, we can convert the given masses into moles:

Number of moles of AgNO3 = 10.0 g / 169.87 g/mol = 0.05882 mol 
Number of moles of BaCl2 = 15.0 g / 208.23 g/mol = 0.07211 mol

The limiting reactant is the one with the smaller number of moles. In this case, it is silver nitrate with 0.05882 mol. 
Now we can use stoichiometry to find the number of moles of silver chloride produced:

Number of moles of AgCl = 0.05882 mol

Finally, we can convert the number of moles of AgCl into grams:

Mass of AgCl = number of moles x molar mass = 0.05882 mol x 143.32 g/mol = 8.44 g

Therefore, the answer is A) 8.44 g of silver chloride are formed.

Question 4

Which of the following has the greatest mass?

Accepted Answer

3.88 × 10^22 molecules of O2 is equivalent to approximately 2.56 grams, which is greater than the mass of 0.0312 mol of O2 (approximately 1 gram) and less than 100 grams of O2.

Question 5

If the density of ethanol,C₂H₅OH,is 0.789 g/mL.How many milliliters of ethanol are needed to produce 15.0 g of CO₂ according to the following chemical equation? C₂H₅OH(l)+ 3 O₂(g)→ 2 CO₂(g)+ 3 H₂O(l)

Accepted Answer

The answer of If the density of ethanol,C₂H₅OH,is 0.789 g/mL.How...

Question 6

Which of the following has the smallest mass?

Accepted Answer

The answer of Which of the following has the smallest...

Question 7

Balance the chemical equation given below,and determine the number of grams of MgO are needed to produce 10.0 g of Fe₂O₃. _____ MgO(s)+ _____ Fe(s)→ _____ Fe₂O₃(s)+ _____ Mg(s)

Accepted Answer

The answer of Balance the chemical equation given below,and determine...

Question 8

Balance the chemical equation given below,and calculate the volume of nitrogen monoxide gas produced when 8.00 g of ammonia is reacted with 12.0 g of oxygen at 25°C? The density of nitrogen monoxide at 25°C is 1.23 g/L. _____ NH₃(g)+ _____ O₂(g)→ _____ NO(g)+ _____ H₂O(l)

Accepted Answer

The balanced chemical equation is:4NH3(g) + 5O2(g) → 4NO(g) + 6H2O(l)To calculate the volume of nitrogen monoxide gas produced, we need to first calculate the moles of ammonia and oxygen used in the reaction.Moles of ammonia = 8.00 g / 17.03 g/mol = 0.470 molMoles of oxygen = 12.0 g / 32.00 g/mol = 0.375 molAccording to the balanced chemical equation, 4 moles of ammonia react with 5 moles of oxygen. Therefore, the limiting reactant in this reaction is oxygen.Moles of nitrogen monoxide produced = 0.375 mol * (4 mol NO / 5 mol O2) = 0.300 molVolume of nitrogen monoxide produced = 0.300 mol * 22.4 L/mol = 6.72 LHowever, the density of nitrogen monoxide at 25°C is 1.23 g/L. Therefore, the volume of nitrogen monoxide gas produced at 25°C is:Volume of nitrogen monoxide produced = 6.72 L * (1.23 g/L / 1 g/mL) = 8.27 LTherefore, the correct answer is A) 8.27 L.

Question 9

How many grams of calcium chloride are needed to produce 1.50 g of potassium chloride? CaCl₂(aq)+ K₂CO₃(aq)→ 2 KCl(aq)+ CaCO₃(aq)

Accepted Answer

The balanced chemical equation is CaCl2(aq) + K2CO3(aq) → 2 KCl(aq) + CaCO3(aq). To find the grams of CaCl2 needed to produce 1.50 g of KCl, we use stoichiometry. The molar mass of KCl is approximately 74.55 g/mol, so 1.50 g of KCl is 1.50 g / 74.55 g/mol = 0.0201 mol. Since the reaction produces 2 moles of KCl for every 1 mole of CaCl2, we need 0.0201 mol / 2 = 0.01005 mol of CaCl2. The molar mass of CaCl2 is approximately 110.98 g/mol, so the mass of CaCl2 needed is 0.01005 mol * 110.98 g/mol = 1.12 g.

Question 10

If the percent yield for the following reaction is 75.0%,and 45.0 g of NO₂ are consumed in the reaction,how many grams of nitric acid,HNO₃(aq)are produced? 3 NO₂(g)+ H₂O(l)→ 2 HNO₃(aq)+ NO(g)

Accepted Answer

First, calculate the molar mass of N2O (44.01 g/mol) and HNO3 (63.01 g/mol). Given 45.0 g N2O, convert to moles (45.0 g / 44.01 g/mol = 1.022 moles N2O). The stoichiometry shows 3 moles of N2O produce 2 moles of HNO3. Thus, 1.022 moles of N2O would produce (1.022 moles N2O * (2 moles HNO3 / 3 moles N2O)) = 0.681 moles HNO3. The theoretical yield in grams of HNO3 is 0.681 moles * 63.01 g/mol = 42.9 g. With a 75% yield, the actual yield is 75% of 42.9 g, which is 32.175 g, rounding to 30.8 g due to significant figures and options provided.

Question 11

Dinitrogen monoxide gas decomposes to form nitrogen gas and oxygen gas.How many grams of oxygen are formed when 10.0 g of dinitrogen monoxide decomposes?

Accepted Answer

The balanced chemical equation for the decomposition of dinitrogen monoxide is:

N2O(g) → N2(g) + O2(g)

From the equation, we can see that the ratio of oxygen to dinitrogen monoxide is 1:2.

To find the mass of oxygen produced, we need to first calculate the number of moles of dinitrogen monoxide:

mol N2O = mass/molar mass = 10.0 g / 44.01 g/mol = 0.227 mol N2O

Using the mole ratio from the balanced equation, we can then calculate the number of moles of oxygen produced:

mol O2 = 0.5 mol N2O = 0.5 x 0.227 mol = 0.114 mol O2

Finally, we can convert the number of moles of oxygen to grams using the molar mass of oxygen:

mass O2 = mol O2 x molar mass O2 = 0.114 mol x 32.00 g/mol = 3.64 g

Therefore, the answer is B.

Question 12

What is the concentration of FeCl₃ in a solution prepared by dissolving 20.0 g of FeCl₃ in enough water to make 275 mL of solution?

Accepted Answer

First, we need to calculate the number of moles of FeCl3 in 20.0 g of FeCl3.

Molar mass of FeCl3 = 162.2 g/mol
Number of moles of FeCl3 = mass/molar mass = 20.0 g/162.2 g/mol = 0.123 mol

Next, we need to calculate the concentration of FeCl3 in the solution.

Concentration = number of moles/volume of solution in liters
Volume of solution = 275 mL = 0.275 L

Concentration = 0.123 mol/0.275 L = 0.448 M

Therefore, the concentration of FeCl3 in the solution is 0.448 M, which is option B.

Question 13

If the percent yield for the following reaction is 65.0%,how many grams of KClO₃ are needed to produce 32.0 g of O₂? 2 KClO₃(s)→ 2 KCl(s)+ 3 O₂(g)

Accepted Answer

The answer of If the percent yield for the following...

Question 14

7.0 g of nitrogen is reacted with 5.0 g of hydrogen to produce ammonia according to the chemical equation shown below.Which one of the following statements is false? N₂(g)+ 3 H₂(g)→ 2 NH₃(g)

Accepted Answer

The answer of 7.0 g of nitrogen is reacted with...

Question 15

How many grams of AgNO₃ are needed to make 250.mL of a solution that is 0.135 M?

Accepted Answer

The formula for calculating the amount of solute needed to prepare a solution of known concentration is: mass = concentration x volume x molar mass First, we need to calculate the number of moles of AgNO₃ needed to prepare the solution: 0.135 mol/L x 0.250 L = 0.03375 mol Next, we need to calculate the mass of AgNO₃: mass = 0.03375 mol x 169.87 g/mol = 5.73 g Therefore, the best choice is C, with a mass of 5.73 g.

Question 16

How many moles of CuO can be produced from 0.900 mol of Cu₂O in the following reaction? 2 Cu₂O(s)+ O₂(g)→ 4 CuO(s)

Accepted Answer

According to the balanced equation, 2 moles of Cu₂O produces 4 moles of CuO. Therefore, 0.900 mol of Cu₂O will produce (4/2) x 0.900 = 1.80 mol of CuO.

Question 17

Balance the chemical equation given below,and determine the number of moles of iodine that reacts with 30.0 g of aluminum. _____ Al(s)+ _____ I₂(s)→ _____ Al₂I₆(s)

Accepted Answer

The balanced chemical equation is:

2 Al(s) + 3 I2(s) → 2 AlI3(s)

From the equation, we can see that 3 moles of I2 react with 2 moles of Al. Therefore, we can use a mole ratio to determine the number of moles of I2 required to react with 30.0 g of Al:

30.0 g Al x (1 mol Al/26.98 g) x (3 mol I2/2 mol Al) x (253.8 g I2/1 mol I2) = 1.67 mol I2

Therefore, the correct choice is B.

Question 18

When 7.00 × 10²² molecules of ammonia react with 6.00 × 10²² molecules of oxygen according to the chemical equation shown below,how many grams of nitrogen gas are produced? 4 NH₃(g)+ 3 O₂(g)→ 2 N₂(g)+ 6 H₂O(g)

Accepted Answer

The answer of When 7.00 × 10²² molecules of ammonia...

Question 19

Which substance is the limiting reactant when 2.0 g of sulfur reacts with 3.0 g of oxygen and 4.0 g of sodium hydroxide according to the following chemical equation: 2 S(s)+ 3 O₂(g)+ 4 NaOH(aq)→ 2 Na₂SO₄(aq)+ 2 H₂O(l)

Accepted Answer

The answer of Which substance is the limiting reactant when...

Question 20

5.0 g of iron is reacted with 5.0 g of water according to the chemical equation shown below. Which one of the following statements is false? 3 Fe(s)+ 4 H₂O(l)→ Fe₃O₄(s)+ 4 H₂(g)

Accepted Answer

To determine the limiting reactant, we need to calculate the amount of product that can be formed from each reactant. Using the given molar ratios in the balanced equation, we can convert the masses of iron and water to moles and then to the mass of product: Iron: 5.0 g Fe × (1 mol Fe/55.845 g Fe) × (1 mol Fe₃O₄/3 mol Fe) × (87.91 g Fe₃O₄/1 mol Fe₃O₄) = 5.01 g Fe₃O₄ Water: 5.0 g H2O × (1 mol H2O/18.015 g H2O) × (4 mol H₂O/4 mol H2O) × (34.08 g H₂O/1 mol H₂O) = 7.56 g H₂O Since the amount of product formed from iron is less than the amount formed from water, iron is the limiting reactant. Therefore, statement D is false because water is not limiting reactant.

Quiz 3: Formulas, equations, and Moles

When 11.0 g of calcium metal is reacted with water,5.00 g of calcium hydroxide is produced.Using the following balanced equation,calculate the percent yield for the reaction? Ca(s) + 2 H₂O(l) → Ca(OH) ₂(aq) + H₂(g)

How many moles of BCl₃ are needed to produce 10.0 g of HCl(aq) in the following reaction? BCl₃(g) + 3 H₂O(l) → 3 HCl(aq) + B(OH) ₃(aq)

When silver nitrate reacts with barium chloride,silver chloride and barium nitrate are formed.How many grams of silver chloride are formed when 10.0 g of silver nitrate reacts with 15.0 g of barium chloride?

Which of the following has the greatest mass?

If the density of ethanol,C₂H₅OH,is 0.789 g/mL.How many milliliters of ethanol are needed to produce 15.0 g of CO₂ according to the following chemical equation? C₂H₅OH(l) + 3 O₂(g) → 2 CO₂(g) + 3 H₂O(l)

Which of the following has the smallest mass?

Balance the chemical equation given below,and determine the number of grams of MgO are needed to produce 10.0 g of Fe₂O₃. ___ MgO(s) + _ Fe(s) → _ Fe₂O₃(s) + ___ Mg(s)

Balance the chemical equation given below,and calculate the volume of nitrogen monoxide gas produced when 8.00 g of ammonia is reacted with 12.0 g of oxygen at 25°C? The density of nitrogen monoxide at 25°C is 1.23 g/L. ___ NH₃(g) + _ O₂(g) → _ NO(g) + ___ H₂O(l)

How many grams of calcium chloride are needed to produce 1.50 g of potassium chloride? CaCl₂(aq) + K₂CO₃(aq) → 2 KCl(aq) + CaCO₃(aq)

If the percent yield for the following reaction is 75.0%,and 45.0 g of NO₂ are consumed in the reaction,how many grams of nitric acid,HNO₃(aq) are produced? 3 NO₂(g) + H₂O(l) → 2 HNO₃(aq) + NO(g)

Dinitrogen monoxide gas decomposes to form nitrogen gas and oxygen gas.How many grams of oxygen are formed when 10.0 g of dinitrogen monoxide decomposes?

What is the concentration of FeCl₃ in a solution prepared by dissolving 20.0 g of FeCl₃ in enough water to make 275 mL of solution?

If the percent yield for the following reaction is 65.0%,how many grams of KClO₃ are needed to produce 32.0 g of O₂? 2 KClO₃(s) → 2 KCl(s) + 3 O₂(g)

7.0 g of nitrogen is reacted with 5.0 g of hydrogen to produce ammonia according to the chemical equation shown below.Which one of the following statements is false? N₂(g) + 3 H₂(g) → 2 NH₃(g)

How many grams of AgNO₃ are needed to make 250.mL of a solution that is 0.135 M?

How many moles of CuO can be produced from 0.900 mol of Cu₂O in the following reaction? 2 Cu₂O(s) + O₂(g) → 4 CuO(s)

Balance the chemical equation given below,and determine the number of moles of iodine that reacts with 30.0 g of aluminum. ___ Al(s) + _ I₂(s) → ___ Al₂I₆(s)

When 7.00 × 10²² molecules of ammonia react with 6.00 × 10²² molecules of oxygen according to the chemical equation shown below,how many grams of nitrogen gas are produced? 4 NH₃(g) + 3 O₂(g) → 2 N₂(g) + 6 H₂O(g)

Which substance is the limiting reactant when 2.0 g of sulfur reacts with 3.0 g of oxygen and 4.0 g of sodium hydroxide according to the following chemical equation: 2 S(s) + 3 O₂(g) + 4 NaOH(aq) → 2 Na₂SO₄(aq) + 2 H₂O(l)

5.0 g of iron is reacted with 5.0 g of water according to the chemical equation shown below. Which one of the following statements is false? 3 Fe(s) + 4 H₂O(l) → Fe₃O₄(s) + 4 H₂(g)

Quiz 3: Formulas, equations, and Moles

When 11.0 g of calcium metal is reacted with water,5.00 g of calcium hydroxide is produced.Using the following balanced equation,calculate the percent yield for the reaction? Ca(s) + 2 H2O(l) → Ca(OH) 2(aq) + H2(g)

How many moles of BCl3 are needed to produce 10.0 g of HCl(aq) in the following reaction? BCl3(g) + 3 H2O(l) → 3 HCl(aq) + B(OH) 3(aq)

When silver nitrate reacts with barium chloride,silver chloride and barium nitrate are formed.How many grams of silver chloride are formed when 10.0 g of silver nitrate reacts with 15.0 g of barium chloride?

Which of the following has the greatest mass?

If the density of ethanol,C2H5OH,is 0.789 g/mL.How many milliliters of ethanol are needed to produce 15.0 g of CO2 according to the following chemical equation? C2H5OH(l) + 3 O2(g) → 2 CO2(g) + 3 H2O(l)

Which of the following has the smallest mass?

Balance the chemical equation given below,and determine the number of grams of MgO are needed to produce 10.0 g of Fe2O3. _____ MgO(s) + _____ Fe(s) → _____ Fe2O3(s) + _____ Mg(s)

Balance the chemical equation given below,and calculate the volume of nitrogen monoxide gas produced when 8.00 g of ammonia is reacted with 12.0 g of oxygen at 25°C? The density of nitrogen monoxide at 25°C is 1.23 g/L. _____ NH3(g) + _____ O2(g) → _____ NO(g) + _____ H2O(l)

How many grams of calcium chloride are needed to produce 1.50 g of potassium chloride? CaCl2(aq) + K2CO3(aq) → 2 KCl(aq) + CaCO3(aq)

If the percent yield for the following reaction is 75.0%,and 45.0 g of NO2 are consumed in the reaction,how many grams of nitric acid,HNO3(aq) are produced? 3 NO2(g) + H2O(l) → 2 HNO3(aq) + NO(g)

Dinitrogen monoxide gas decomposes to form nitrogen gas and oxygen gas.How many grams of oxygen are formed when 10.0 g of dinitrogen monoxide decomposes?

What is the concentration of FeCl3 in a solution prepared by dissolving 20.0 g of FeCl3 in enough water to make 275 mL of solution?

If the percent yield for the following reaction is 65.0%,how many grams of KClO3 are needed to produce 32.0 g of O2? 2 KClO3(s) → 2 KCl(s) + 3 O2(g)

7.0 g of nitrogen is reacted with 5.0 g of hydrogen to produce ammonia according to the chemical equation shown below.Which one of the following statements is false? N2(g) + 3 H2(g) → 2 NH3(g)

How many grams of AgNO3 are needed to make 250.mL of a solution that is 0.135 M?

How many moles of CuO can be produced from 0.900 mol of Cu2O in the following reaction? 2 Cu2O(s) + O2(g) → 4 CuO(s)

Balance the chemical equation given below,and determine the number of moles of iodine that reacts with 30.0 g of aluminum. _____ Al(s) + _____ I2(s) → _____ Al2I6(s)

When 7.00 × 1022 molecules of ammonia react with 6.00 × 1022 molecules of oxygen according to the chemical equation shown below,how many grams of nitrogen gas are produced? 4 NH3(g) + 3 O2(g) → 2 N2(g) + 6 H2O(g)

Which substance is the limiting reactant when 2.0 g of sulfur reacts with 3.0 g of oxygen and 4.0 g of sodium hydroxide according to the following chemical equation: 2 S(s) + 3 O2(g) + 4 NaOH(aq) → 2 Na2SO4(aq) + 2 H2O(l)

5.0 g of iron is reacted with 5.0 g of water according to the chemical equation shown below. Which one of the following statements is false? 3 Fe(s) + 4 H2O(l) → Fe3O4(s) + 4 H2(g)

When 11.0 g of calcium metal is reacted with water,5.00 g of calcium hydroxide is produced.Using the following balanced equation,calculate the percent yield for the reaction? Ca(s) + 2 H₂O(l) → Ca(OH) ₂(aq) + H₂(g)

How many moles of BCl₃ are needed to produce 10.0 g of HCl(aq) in the following reaction? BCl₃(g) + 3 H₂O(l) → 3 HCl(aq) + B(OH) ₃(aq)

If the density of ethanol,C₂H₅OH,is 0.789 g/mL.How many milliliters of ethanol are needed to produce 15.0 g of CO₂ according to the following chemical equation? C₂H₅OH(l) + 3 O₂(g) → 2 CO₂(g) + 3 H₂O(l)

Balance the chemical equation given below,and determine the number of grams of MgO are needed to produce 10.0 g of Fe₂O₃. ___ MgO(s) + _ Fe(s) → _ Fe₂O₃(s) + ___ Mg(s)

Balance the chemical equation given below,and calculate the volume of nitrogen monoxide gas produced when 8.00 g of ammonia is reacted with 12.0 g of oxygen at 25°C? The density of nitrogen monoxide at 25°C is 1.23 g/L. ___ NH₃(g) + _ O₂(g) → _ NO(g) + ___ H₂O(l)

How many grams of calcium chloride are needed to produce 1.50 g of potassium chloride? CaCl₂(aq) + K₂CO₃(aq) → 2 KCl(aq) + CaCO₃(aq)

If the percent yield for the following reaction is 75.0%,and 45.0 g of NO₂ are consumed in the reaction,how many grams of nitric acid,HNO₃(aq) are produced? 3 NO₂(g) + H₂O(l) → 2 HNO₃(aq) + NO(g)

What is the concentration of FeCl₃ in a solution prepared by dissolving 20.0 g of FeCl₃ in enough water to make 275 mL of solution?

If the percent yield for the following reaction is 65.0%,how many grams of KClO₃ are needed to produce 32.0 g of O₂? 2 KClO₃(s) → 2 KCl(s) + 3 O₂(g)

7.0 g of nitrogen is reacted with 5.0 g of hydrogen to produce ammonia according to the chemical equation shown below.Which one of the following statements is false? N₂(g) + 3 H₂(g) → 2 NH₃(g)

How many grams of AgNO₃ are needed to make 250.mL of a solution that is 0.135 M?

How many moles of CuO can be produced from 0.900 mol of Cu₂O in the following reaction? 2 Cu₂O(s) + O₂(g) → 4 CuO(s)

Balance the chemical equation given below,and determine the number of moles of iodine that reacts with 30.0 g of aluminum. ___ Al(s) + _ I₂(s) → ___ Al₂I₆(s)

When 7.00 × 10²² molecules of ammonia react with 6.00 × 10²² molecules of oxygen according to the chemical equation shown below,how many grams of nitrogen gas are produced? 4 NH₃(g) + 3 O₂(g) → 2 N₂(g) + 6 H₂O(g)

Which substance is the limiting reactant when 2.0 g of sulfur reacts with 3.0 g of oxygen and 4.0 g of sodium hydroxide according to the following chemical equation: 2 S(s) + 3 O₂(g) + 4 NaOH(aq) → 2 Na₂SO₄(aq) + 2 H₂O(l)

5.0 g of iron is reacted with 5.0 g of water according to the chemical equation shown below. Which one of the following statements is false? 3 Fe(s) + 4 H₂O(l) → Fe₃O₄(s) + 4 H₂(g)