1.
Acids taste sour.
Correct Answer
A. True
Explanation
Acids taste sour because they release hydrogen ions (H+) when dissolved in water. These hydrogen ions react with taste buds on the tongue, triggering a sour taste sensation. This is why substances like lemon juice, vinegar, and citrus fruits taste sour, as they contain acidic compounds.
2.
Acids contain (OH) ions.
Correct Answer
B. False
Explanation
Acids do not contain (OH) ions. In fact, acids contain hydrogen ions (H+), while bases contain hydroxide ions (OH-). The presence of (OH) ions indicates the presence of a base rather than an acid. Therefore, the statement that acids contain (OH) ions is false.
3.
Bases react with metals.
Correct Answer
A. True
Explanation
Bases (alkalis) react with metals to form metal hydroxides and hydrogen gas. This is a common reaction observed in chemistry, where the base accepts a proton from the metal, resulting in the formation of the metal hydroxide and hydrogen gas being released.
4.
Strong acids are considered a 12-14 on the pH scale.
Correct Answer
B. False
Explanation
Strong acids are actually considered to be between 0-3 on the pH scale, not 12-14. The pH scale ranges from 0 to 14, with 0 being the most acidic and 14 being the most basic. Strong acids have a low pH value, indicating a high concentration of hydrogen ions. Therefore, the correct answer is False.
5.
Acids would have hydrogen in their chemical formula.
Correct Answer
A. True
Explanation
Acids are substances that release hydrogen ions (H+) when dissolved in water. The presence of hydrogen ions is a characteristic feature of acids, and it is reflected in their chemical formula. Acids typically have the element hydrogen (H) in their formula, indicating their ability to donate hydrogen ions. Therefore, it is true that acids would have hydrogen in their chemical formula.
6.
Bases are proton donors.
Correct Answer
B. False
Explanation
Bases are not proton donors, but rather proton acceptors. They have the ability to accept a proton from an acid, forming a conjugate acid. This is in contrast to acids, which are proton donors. Therefore, the correct answer is false.
7.
Bases break up fats.
Correct Answer
A. True
Explanation
Bases, also known as alkaline substances, have the ability to break up fats through a process called saponification. When a base reacts with fats, it forms soap molecules, which help to emulsify and dissolve the fats. This process is commonly used in soap making and cleaning products. Therefore, the statement "Bases break up fats" is true.
8.
Bases turn litmus paper red.
Correct Answer
B. False
Explanation
Litmus paper turns red in the presence of an acid and blue in the presence of a base. Therefore, bases do not turn litmus paper red. The correct answer is False.
9.
Litmus paper that does not change color would indicate a pH of 7.
Correct Answer
A. True
Explanation
If litmus paper does not change color, it means that it remains the same color as it was before being exposed to a substance. Litmus paper is commonly used to test the pH of a substance, with red indicating acidity and blue indicating alkalinity. Since litmus paper that does not change color would indicate a pH of 7, which is considered neutral, the statement is true.
10.
Acids would have OH in their chemical formula.
Correct Answer
B. False
Explanation
Acids do not have OH in their chemical formula. Acids are substances that release hydrogen ions (H+) when dissolved in water. The presence of OH in a chemical formula indicates a base, not an acid. Acids typically have hydrogen (H) as the first element in their formula, such as HCl (hydrochloric acid) or H2SO4 (sulfuric acid).
11.
When you combine an acid and a base a salt and water are formed.
Correct Answer
A. True
Explanation
When an acid and a base are combined, a chemical reaction called neutralization occurs. During this reaction, the hydrogen ions from the acid react with the hydroxide ions from the base to form water. Additionally, the positive ions from the base combine with the negative ions from the acid to form a salt. Therefore, when an acid and a base are combined, both a salt and water are indeed formed.
12.
A neutralization reaction is a single replacement reaction.
Correct Answer
B. False
Explanation
The statement that a neutralization reaction is a single replacement reaction is false. A neutralization reaction is actually a type of double displacement reaction, where an acid reacts with a base to form a salt and water. In a single replacement reaction, one element replaces another in a compound. Therefore, the correct answer is false.
13.
Drano is a strong acid.
Correct Answer
B. False
Explanation
Drano is not a strong acid, but rather a strong base. It is commonly used as a drain cleaner and contains sodium hydroxide, which is a strong base. Strong acids, on the other hand, have a low pH and can easily donate protons, while strong bases have a high pH and can easily accept protons. Since Drano is a strong base, the correct answer is false.
14.
A pH of 9 is considered neutral.
Correct Answer
B. False
Explanation
A pH of 9 is not considered neutral. In fact, a pH of 7 is considered neutral. A pH value below 7 indicates acidity, while a pH value above 7 indicates alkalinity. Therefore, a pH of 9 is considered alkaline or basic, not neutral.
15.
A pH of 3-6 are considered weak acids.
Correct Answer
A. True
Explanation
A pH of 3-6 indicates a higher concentration of hydrogen ions in a solution, which makes it acidic. Weak acids have a pH value within this range, indicating that they partially dissociate in water and release a small number of hydrogen ions. Therefore, the statement that a pH of 3-6 is considered weak acids is true.