Acids and Bases

Front

Acids taste

Back

sour

Answer explanation

Acids are known for their sour taste, which is a characteristic that distinguishes them from other flavors like sweet, salty, or bitter. Therefore, the correct answer is 'sour'.

Front

Acids turn blue litmus paper

Back

red

Answer explanation

Acids are known to turn blue litmus paper red. This is a classic indicator reaction, where the presence of an acid changes the color of the litmus paper from blue to red, confirming its acidic nature.

Front

Strong acids have a pH of

Back

1

Answer explanation

Strong acids have a pH of 1, indicating a high concentration of hydrogen ions. A pH of 1 is characteristic of strong acids, while values like 4, 6, and 7 represent weaker acids or neutral solutions.

Front

Bases taste

Back

bitter

Answer explanation

Bases typically taste bitter due to their chemical properties. This distinguishes them from acids, which are sour, and other taste categories like sweet and salty.

Front

Bases turn red litmus paper

Back

blue

Answer explanation

Bases turn red litmus paper blue, indicating a basic pH. The other options, red, green, and pink, do not represent the correct reaction of bases with litmus paper.

Front

Strong bases have a pH of

Back

13

Answer explanation

Strong bases typically have a pH greater than 12. A pH of 13 indicates a strong base, while lower values like 1, 4, and 9 represent acidic or weakly basic solutions. Therefore, the correct answer is 13.

Front

7 on the pH scale means a liquid is

Back

neutral

Answer explanation

A pH of 7 indicates that a liquid is neutral, meaning it is neither acidic nor basic. Acids have a pH less than 7, while bases have a pH greater than 7.

Front

How much stronger is an acid with a pH of 2 compared to an acid with a pH of 4?

Back

100 x

Answer explanation

The pH scale is logarithmic, meaning each whole number change represents a tenfold change in acidity. Therefore, an acid with a pH of 2 is 100 times stronger than one with a pH of 4.

Front

How much stronger is an acid with a pH of 2 compared to an acid with a pH of 6?

Back

10, 000 x

Answer explanation

The pH scale is logarithmic, meaning each whole number change represents a tenfold change in acidity. A pH of 2 is 4 units lower than a pH of 6, so the acid with pH 2 is 10,000 times stronger than the one with pH 6.

Front

How much stronger is a base with a pH of 10 compared to a base with a pH of 9?

Back

10 x

Answer explanation

A pH difference of 1 unit corresponds to a tenfold difference in hydrogen ion concentration. Therefore, a base with a pH of 10 is 10 times stronger than a base with a pH of 9.