Acid and Base Vocabulary

What is an Acid (산, 酸)?

• A. A substance that changes color to indicate the presence of an acid or a base.

• B. A substance with a pH level less than 7, which releases hydrogen ions (H+) when dissolved in water.

• C. A liquid solution containing a pH-sensitive dye used to measure the pH of substances.

• D. A compound formed when the hydrogen ions from an acid react with the hydroxide ions from a base.

Define a Base (염기, 碱).

• A. A positively charged ion formed when an acid dissolves in water.

• B. A substance with a pH level greater than 7, which releases hydroxide ions (OH-) when dissolved in water.

• C. A substance that changes color to indicate the presence of an acid or a base.

• D. A compound used exclusively for seasoning food.

What is the pH Scale (pH 척도, pH 标度)?

• A. A scale measuring the temperature of a substance.

• B. A scale that measures the electrical conductivity of a substance.

• C. A scale that measures the acidity or alkalinity of a substance, ranging from 0 to 14.

• D. A scale used to measure the concentration of hydrogen ions in a solution.

What does Neutral (중성, 中性) mean in this context?

• A. A substance with a pH of 7, neither acidic nor basic.

• B. A compound formed from acid-base reactions.

• C. A type of indicator paper.

• D. A soluble base used in cleaning products.

Define an Indicator (지시약, 指示剂).

• A. A substance with a pH level less than 7.

• B. A substance that changes color to indicate the presence of an acid or a base.

• C. A soluble base used in cleaning products.

• D. A paper used to filter chemical solutions.

What is Litmus Paper (리트머스 종이, 石蕊试纸)?

• A. A paper used to filter chemical solutions.

• B. A type of indicator paper that turns red in the presence of an acid and blue in the presence of a base.

• C. A paper that measures the concentration of hydrogen ions in a solution.

• D. A liquid solution used to indicate pH levels.

What is a Hydrogen Ion (H+) (수소 이온, 氢离子)?

• A. A negatively charged ion formed when a base dissolves in water.

• B. A compound formed from acid-base reactions.

• C. A positively charged ion formed when an acid dissolves in water.

• D. A type of pH indicator.

Define Hydroxide Ion (OH-) (수산화 이온, 氢氧根离子).

• A. A positively charged ion associated with acids.

• B. A type of pH indicator.

• C. A negatively charged ion formed when a base dissolves in water.

• D. A substance used to increase the pH level in soils.

What is Neutralization (중화 반응, 中和反应)?

• A. The increase in pH level when a base is added to a solution.

• B. The chemical reaction between an acid and a base, resulting in the formation of water and a salt.

• C. The process of removing hydrogen ions from a solution.

• D. The method of separating compounds using filtration.

What constitutes a Salt (염, 盐) in this context?

• A. A compound used exclusively for seasoning food.

• B. A compound formed when the hydrogen ions from an acid react with the hydroxide ions from a base.

• C. A negatively charged ion in a chemical reaction.

• D. A substance with a neutral pH, such as water.