pH

Question 1

pH scale

Answer 1

pH scale is an indication of the hydrogen ion concentration and runs from below 0 to above 14.

Question 2

In a neutral solution the concentration of H+(aq) is ________ compared to OH¯(aq) ions greater / less / the same

Answer 2

In a neutral solution the concentration of H+(aq) is the same compared to OH¯(aq) ions

        H+(aq)  = OH¯(aq)

Question 3

Dissociation of water into ions

Answer 3

H2O ->

Question 4

Acidic solutions have
higher / lower / same
concentration of H+ (aq) ions to OH¯(aq) and have a pH
of 7 / below 7 / above 7.

Answer 4

Acidic solutions have higher concentration of H+ (aq) ions to OH¯(aq) and have a pH below 7

Question 5

Alkaline solutions have
higher / lower / same
concentration of H+ (aq) ions to OH¯(aq) and have a pH
of 7 / below 7 / above 7.

Answer 5

Alkaline solutions have lower concentration of H+ (aq) ions to OH¯(aq) and have a pH above 7

Question 6

Diluting an acid with water will..

Answer 6

Dilution of an acidic solution with water will decrease the concentration of H+(aq) and the pH will increase towards 7.

Question 7

Diluting an alkali with water will..

Answer 7

Dilution of an alkaline solution with water will decrease the concentration of OH-(aq) and the pH will decrease towards 7.

Question 8

Dissolve to form acids

Answer 8

Soluble non-metal oxides
e.g. carbon dioxide, sulphur dioxide, nitrogen dioxide.
Remember blowing through a straw into universal indicator turns it orange (acid breath).

Question 9

Dissolve to form alkalis

Answer 9

Soluble metal oxides
e.g. calcium oxide, lithium oxide, barium oxide.
See page 8 of the Data book

Question 10

Metal oxides, metal hydroxides, metal carbonates and ammonia

Are types of what?

Answer 10

They all neutralise acids and are called bases.

Question 11

Soluble bases

Answer 11

Bases that dissolve in water form alkaline solutions. - Alkalis