Which one of the following must be added to dilute hydrochloric acid to produce hydrogen?

A. Iron

B. Iron sulfide

C. Copper chloride

D. Sulfur

Answer Explanation:

A. Iron (Correct Answer): Iron can react with hydrochloric acid to produce hydrogen gas according to the following reaction:

2HCl + Fe => FeCl2 + H2

So, adding iron to dilute hydrochloric acid would produce hydrogen gas.

B. Iron sulfide: Iron sulfide may react with hydrochloric acid, but it does not directly produce hydrogen gas. The reaction would likely produce hydrogen sulfide gas instead.

C. Copper chloride: Copper chloride does not react with hydrochloric acid to produce hydrogen gas. The reaction between copper chloride and hydrochloric acid would likely produce copper chloride and hydrogen chloride gas.

D. Sulfur: Sulfur does not react with hydrochloric acid to produce hydrogen gas. The reaction between sulfur and hydrochloric acid would likely produce hydrogen sulfide gas.

Therefore, the Correct Answer is A.

Q #1: What is produced when an acid reacts with ammonia?

A. Water

B. Ammonia and Water

C. Ammonium salt

D. Hydrogen gas

Answer Explanation

A) Water: Water is not typically produced when an acid reacts with ammonia. Water may be present in the reaction mixture, but it is not a direct product of the reaction between the acid and ammonia.

B) Ammonium chloride: Water and ammonia are not typically produced when an acid reacts with ammonia.

C) Ammonium salt (Correct Answer): When an acid reacts with ammonia, an ammonium salt is typically formed. The specific ammonium salt produced depends on the acid used in the reaction.

D) Hydrogen gas: Hydrogen gas is not typically produced when an acid reacts with ammonia. The reaction between an acid and ammonia does not involve the liberation of hydrogen gas.
Q #2: When acids and bases react together, we call this a:

A. Neutralization reaction.

B. Decomposition reaction.

C. Synthesis reaction.

D. Redox reaction.

Answer Explanation

A. Neutralization reaction. (Correct Answer): When acids and bases react, they undergo a neutralization reaction, resulting in the formation of water and a salt. In this reaction, the acidic properties of the acid are neutralized by the basic properties of the base.

B. Decomposition reaction: A decomposition reaction involves the breakdown of a compound into smaller substances. It does not typically describe the reaction between acids and bases.

C. Synthesis reaction: A synthesis reaction involves the formation of a compound from simpler substances. It does not typically describe the reaction between acids and bases.

D. Redox reaction: A redox reaction involves the transfer of electrons between reactants. While redox reactions can occur in certain acid-base reactions, they are not specific to the reaction between acids and bases. The typical reaction between acids and bases involves proton transfer rather than electron transfer. Therefore, "neutralization reaction" is a more specific and accurate term for this type of reaction.
Q #3: Why do farmers use ammonium salts on their fields?

A. To prevent soil erosion

B. To increase soil acidity

C. To help plants grow (as fertilizers)

D. To reduce soil salinity

Answer Explanation

A) To prevent soil erosion: While certain soil management practices may involve measures to prevent erosion, the use of ammonium salts specifically does not directly relate to preventing soil erosion.

B) To increase soil acidity: Ammonium salts, such as ammonium sulfate, can actually decrease soil pH, making the soil more acidic. However, this is not typically the primary reason farmers use these salts.

C) To help plants grow (as fertilizers) (Correct Answer): Ammonium salts are commonly used as fertilizers because they provide essential nitrogen to plants in a form that they can readily absorb. Nitrogen is a crucial nutrient for plant growth, and ammonium salts serve as a source of nitrogen for crops.

D) To reduce soil salinity: Ammonium salts are not typically used to reduce soil salinity. Salinity issues in soil are typically addressed through other methods such as leaching or soil amendments, rather than the addition of ammonium salts.

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Which one of the following must be added to dilute hydrochloric acid to produce hydrogen?

More Questions on TEAS 7 Science

Q #1: What is produced when an acid reacts with ammonia?

Answer Explanation

Q #2: When acids and bases react together, we call this a:

Answer Explanation

Q #3: Why do farmers use ammonium salts on their fields?

Answer Explanation

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