Acids

Question 1

What ion do all acids release in aqueous solutions?

Answer 1

Hydrogen ions (H⁺).

Question 2

Give an example of a weak acid.

Answer 2

Ethanoic acid (CH₃COOH).

Question 3

Give an example of a strong acid.

Answer 3

Hydrochloric acid (HCl).

Question 4

What is the general word equation for a reaction between an acid and a metal?

Answer 4

Acid + Metal → Salt + Hydrogen.

Question 5

What is the general word equation for a reaction between an acid and a base?

Answer 5

Acid + Base → Salt + Water.

Question 6

What is the general word equation for a reaction between an acid and a carbonate?

Answer 6

Acid + Carbonate → Salt + Water + Carbon dioxide.

Question 7

What is the formula of sulfuric acid?

Answer 7

H₂SO₄.

Question 8

What is the formula of nitric acid?

Answer 8

HNO₃.

Question 9

What is the formula of hydrochloric acid?

Answer 9

HCl.

Question 10

What is an alkali?

Answer 10

A soluble base that produces OH⁻ ions in water.

Question 11

What does litmus indicate in acidic and alkaline solutions?

Answer 11

Acid: Red

Alkali: Blue

Neutral: Purple

Question 12

What does phenolphthalein indicate in acidic and alkaline solutions?

Answer 12

Acid: Colourless

Alkali: Pink

Neutral: Colourless

Question 13

What does methyl orange indicate in acidic and alkaline solutions?

Answer 13

Acid: Red

Alkali: Yellow

Neutral: Yellow

Question 14

What is observed when a metal reacts with an acid?

Answer 14

Effervescence (bubbling) due to hydrogen gas release.

Question 15

What is the Test for Hydrogen?

Answer 15

Insert a lit splint into the gas – hydrogen burns with a ‘squeaky pop’ sound.

Question 16

How are acids and bases defined in terms of proton transfer?

Answer 16

Acid: A proton donor (it gives away H⁺ ions)

Base: A proton acceptor (it takes in H⁺ ions)