properties of acid and bases

Question 1

What is an acid?

Answer 1

An acid is a substance that typically releases hydrogen ions (H+) into an aqueous solution (containing water) Other properties include:

• they are corrosive
• have a sour taste
• conduct electricity->release ions
• react with some metals->producing H2 gas and a salt
• turn blue litmus paper red
• are neutralised by bases->producing water and a salt

Question 2

How do we name acids?

Answer 2

When an ion that ends in ATE joins with hydrogen to make an acid, the ATE changes to IC. E.g. Hydrogen +nitrate -> nitric acid.

Question 3

Common acids you need to know!

Answer 3

sulfuric acid: H2SO4
ethanoic acid: CH3COOH
hydrochloric acid: HCl
Nitric acid: HNO3

Question 4

What is a base.

Answer 4

A base is a substance that typically releases hydroxide ions (OH-). If a base can be dissolved in water, it is called an alkali. (Note: some substances that behave as bases do not contain OH in their formula e.g. ammonia: NH3, and the carbonate ion: CO3^2-
Other properties:
-are caustic 
-have a slippery/soapy feel
-have a bitter taste
-conduct electricity-> release ions
-turn red litmus paper blue
-are neutralised by acids-> producing water and a salt

Question 5

How do we name bases?

Answer 5

• Bases contain hydroxide (OH-)

- same as naming ionic compounds

Question 6

what is a pH scale?

Answer 6

The concentration of hydrogen ions (H+) in a solution is measured using the pH scale. A pH scale of 7 means that the substance is neutral. A pH scale of 6-1 means that it is acidic. A pH scale of 8-14 means that it is a base.

Question 7

What does is an acid-base indicator?

Answer 7

An indicator is a chemical that changes to a different colour when added to a solution of an acid or base.