When dilute nitric acid was added to a solution of one of the following chemicals, a gas was evolved. This gas turned a drop of limewater, Ca(OH)2, cloudy, due to the formation of a white precipitate. The chemical was....

The Ca(OH)2 test is for CO2 (SO2 or SO3 will do the same thing) and CO2 comes from .....

To determine which chemical reacts with dilute nitric acid to produce a gas that turns limewater cloudy, we need to consider the possible reactions between nitric acid (HNO3) and the listed chemicals.

a. Ammonia (NH3): Dilute nitric acid does not react with ammonia to produce a gas. Therefore, option a is not the correct answer.

b. Baking soda (NaHCO3): When nitric acid reacts with baking soda, it produces carbon dioxide (CO2) gas, water (H2O), and sodium nitrate (NaNO3). However, this reaction does not cause limewater to turn cloudy. Therefore, option b is not the correct answer.

c. Table salt (NaCl): Dilute nitric acid does not react with table salt to produce a gas. Therefore, option c is not the correct answer.

d. Epsom salts (MgSO4·7H2O): Dilute nitric acid does not react with epsom salts to produce a gas. Therefore, option d is not the correct answer.

e. Bleach (5% NaOCl): When dilute nitric acid reacts with bleach, it produces chlorine gas (Cl2) as one of the products. Chlorine gas turns limewater cloudy due to the formation of a white precipitate, calcium carbonate (CaCO3), which is insoluble in water. Therefore, the correct answer is option e, bleach (5% NaOCl).

So, the chemical that reacts with dilute nitric acid to produce a gas that turns limewater cloudy is bleach (5% NaOCl).

To determine which chemical was responsible for the gas formation and the subsequent reaction with limewater, we can consider the reaction that occurs between nitric acid and each of the possible chemicals.

a. When dilute nitric acid reacts with household ammonia (NH3), no gas is evolved. The reaction between nitric acid and ammonia simply results in the formation of ammonium nitrate (NH4NO3).

b. When dilute nitric acid reacts with baking soda (NaHCO3), carbon dioxide (CO2) gas is evolved. However, this gas does not react with limewater.

c. When dilute nitric acid reacts with table salt (NaCl), no gas is evolved. The reaction between nitric acid and sodium chloride does not produce any gases or precipitates.

d. When dilute nitric acid reacts with epsom salts (MgSO4 · 7H2O), no gas is evolved. The reaction between nitric acid and magnesium sulfate simply results in the formation of magnesium nitrate (Mg(NO3)2).

e. When dilute nitric acid reacts with bleach (5% NaOCl), chlorine gas (Cl2) is evolved. This chlorine gas reacts with limewater (Ca(OH)2) to form a white precipitate of calcium chloride (CaCl2) and water (H2O).

Based on these reactions, the chemical that is responsible for the gas evolution and the formation of a white precipitate when dilute nitric acid is added is bleach (NaOCl) with the equation:

2NaOCl + 2HNO3 → 2NaNO3 + Cl2 + H2O

Therefore, the correct answer is e. bleach (5% NaOCl).