Question

1. Moles of Reactant to Mass of Reactant: Identify the iodide ions and ozone in the balanced chemical equation. Use mole ratio, then convert to grams.

A method used by the EPA for determining the ozone concentration in the air is to pass an air sample through a bubbler containing iodide ions. The iodide ions remove the ozone according to the following reaction:

O₃(g) + 2 I^-(aq) + H₂O(l)  → O₂(g) + I₂(aq) + 2 OH^-(aq)

How many grams of ozone can be removed from the air sample if 5.11 moles of iodide ions are present in the bubbler? Express your answer to two decimal places.

g

2.

Mass of Reactant to Mass of Product and Mass of Reactant: Convert pounds to grams. Then convert grams to moles and use mole ratio. Convert final substance to grams.

Suppose you buy a 90.0 pound propane tank for your gas grill. The combustion of propane gas (C₃H₈) in the presence of oxygen gas produces liquid water and carbon dioxide gas.

a. Write a balanced chemical equation for the combustion of propane. This is not done in WebAssign, just do it on a piece of paper for you to use. Include all state symbols for good measure.

b. How many grams of propane are in the tank? Express your answer to two decimal places, do not use any commas. (1 pound = 454 grams)

g

c. According to the balanced chemical equation for the combustion of propane, how many grams of water will be produced by the combustion of the entire tank? Express your answer to two decimal places, do not use any commas.

g

d. How many grams of oxygen is required for this combustion? Express your answer to two decimal places, do not use any commas.

g

Limiting Reactant - Moles to Moles: Perform separate calculations beginning with each reactant to determine the moles of product. Identify limiting reagent by the smallest amount of product.

Suppose 7.58 moles of propane and 24.0 moles of oxygen are sealed in a container and burned.Which reactant will be the limiting reactant with respect to how much carbon dioxide is produced?

oxygenpropane     

How many moles of carbon dioxide will be produced? Express your answer to two decimal places.

mol

3.

Limiting Reactant - Mass to Mass: Perform two calculations to determine the limiting reactant and therefore the maximum amount of product produced.

The fizz produced when Alka Seltzer tablet is dissolved in water is due to the reaction between sodium bicarbonate (NaHCO₃) and citric acid (H₃C₆H₅O₇).

3 NaHCO₃(aq) + H₃C₆H₅O₇(aq) → 3 CO₂(g) + 3 H₂O(l) + Na₃C₆H₅O₇(aq)

In a certain experiment 5.14 g of sodium bicarbonate and 4.23 g of citric acid are allowed to react.

a. What is the limiting reactant with respect to the production of carbon dioxide?

citric acidsodium bicarbonate     

b. How many grams of carbon dioxide form? Express your answer to two decimal places.

g

4.

Limiting Reactant - Mass to Moles: Perform two calculations to determine how many moles of product can be produced with each reactant. No need to go all the way to grams of product since that is not part of the question.

Wine 'sours' when ethanol (CH₃CH₂OH, sometimes written as EtOH) is oxidized (by O₂) to acetic acid (a component of vinegar sometimes written as HOAc). The balanced equation for the reaction is:

CH₃CH₂OH + O₂  → CH₃COOH + H₂O

Is the chemical equation balanced?

noyes     

If 202 g of ethanol and 194 g of oxygen are sealed in a wine bottle, which is the limiting reactant with respect to the production of vinegar?

oxygenethanol     

5

Limiting Reactant - Mass to Mass: Perform two calculations to determine the limiting reactant and amount of product produced.

Hydrogen cyanide, a highly toxic compound, is made by the following reaction:

2 CH₄(g) + 2 NH₃(g) + 3 O₂(g) → 2 HCN(g) + 6 H₂O(g)

What is the limiting reagent with respect to HCN production if 45.4 g of O₂ are added to 23.8 g of NH₃? (assume CH₄ is in excess)

ammonia

oxygen   

What is the mass of HCN that can be produced from these reactants? Express your answer to two decimal places.

g

6.

Limiting Reactant - Mass to Mass - Percent Yield: Perform two calculations to determine the limiting reactant and theoretical amount of product produced. For percent yield, compare the experimental mass to theoretical mass (experimental / theoretical * 100).

Balance the following equation for the formation of ammonia from nitrogen gas and hydrogen gas (if the coefficient = 1, you must enter 1 into the box):
  N₂ +   H₂ →   NH₃

a. If 7.73 g of nitrogen gas and 5.2 g of hydrogen gas are used, what is the limiting reactant?

nitrogenhydrogen   

b. What is the theoretical yield of ammonia? Express your answer to two decimal places.

g


c. What is the percent yield for this reaction if 9.211762154 g of ammonia are obtained experimentally? Express your answer to two significant figures.

%

Answer 1