Acid Properties & Reactions

What are the properties of acids?

• Acids have a sour taste, turn blue litmus paper red, react with metals to produce hydrogen gas, and have a pH less than 7.

• Acids do not react with metals

• Acids turn red litmus paper blue

• Acids taste sweet

Answer explanation

Acids have a sour taste, turn blue litmus paper red, react with metals to produce hydrogen gas, and have a pH less than 7.

Balance the following acid-base reaction: HCl + NaOH -> NaCl + H2O

• HCl + NaOH -> NaCl + H2O

• NaOH + H2O -> NaCl + HCl

• HCl + NaCl -> NaOH + H2O

• H2O + NaCl -> NaOH + HCl

Answer explanation

The correct balanced acid-base reaction is HCl + NaOH -> NaCl + H2O, where one molecule of HCl reacts with one molecule of NaOH to form one molecule of NaCl and one molecule of H2O.

Identify the type of acid: H2SO4

• Sulfuric acid

• Acetic acid

• Hydrochloric acid

• Nitric acid

Answer explanation

The correct type of acid is Sulfuric acid because the chemical formula H2SO4 corresponds to sulfuric acid.

In an experiment, how can you test for the presence of an acid?

• Smell it

• Use litmus paper

• Taste it directly

• Look at it under a microscope

Answer explanation

To test for the presence of an acid in an experiment, you can use litmus paper, which changes color in the presence of an acid.

What happens when acids react with metals?

• Formation of water and release of oxygen gas

• Formation of metal oxides and release of nitrogen gas

• Formation of salt and release of hydrogen gas

• Formation of acids and release of carbon dioxide gas

Answer explanation

When acids react with metals, they form salt and release hydrogen gas. This is due to the displacement reaction between the acid and the metal, resulting in the formation of a salt and hydrogen gas.

Balance the following acid-base reaction: HNO3 + KOH -> KNO3 + H2O

• 2HNO3 + KOH -> KNO3 + H2O

• HNO3 + KOH -> KNO3 + 2H2O

• HNO3 + 2KOH -> KNO3 + H2O

• 2HNO3 + 2KOH -> 2KNO3 + 2H2O

Answer explanation

To balance the reaction, you need 2 molecules of HNO3 and 2 molecules of KOH to produce 2 molecules of KNO3 and 2 molecules of H2O. Therefore, the balanced equation is 2HNO3 + 2KOH -> 2KNO3 + 2H2O.

Identify the type of acid: HCl

• Carbonic acid

• Nitric acid

• Sulfuric acid

• Hydrochloric acid

Answer explanation

The correct type of acid for HCl is Hydrochloric acid, as indicated by the chemical formula HCl.

How do acids taste?

• Sour

• Sweet

• Salty

• Bitter

Answer explanation

Acids taste sour due to their acidic properties, which trigger sour taste receptors on the tongue.

What is the pH range of acids?

• 1 to 7.99

• 0 to 6.99

• 2 to 5.99

• 0 to 8.99

Answer explanation

The correct pH range of acids is from 0 to 6.99, making the answer choice '0 to 6.99' the accurate option.

Balance the following acid-base reaction: H2SO4 + Ca(OH)2 -> CaSO4 + H2O

• Ca(OH)2 + H2SO4 -> CaSO3 + H2O

• H2SO4 + Ca(OH)2 -> CaSO2 + H2O

• Ca(OH)2 + H2SO4 -> CaSO4 + 2H2O

• Ca(OH)2 + H2SO4 -> CaSO4 + H2O

Answer explanation

To balance the reaction, Ca(OH)2 + H2SO4 -> CaSO4 + 2H2O is correct as it balances the number of atoms on both sides of the equation.