Chemistry

Question 1

What does a chemical formulae tell us?

Answer 1

Which elements are in a compound and how many atoms of each element there are

Question 2

What is an indicator?

Answer 2

A substance that changes colour in acid, alkaline or neutral solutions

Question 3

What will turn red in universal indicator?

Answer 3

Acids

Question 4

What will turn green in universal indicator?

Answer 4

Neutral substances

Question 5

What will turn blue/purple in universal indicator?

Answer 5

Alkalis

Question 6

Give an example of a weak acid

Answer 6

Vinegar

Question 7

Give an example of a weak alkali

Answer 7

Toothpaste

Question 8

Give an example of a strong alkali

Answer 8

Oven cleaner

Question 9

Give an example of a neutral substance

Answer 9

Water

Question 10

What are acids on the pH scale?

Answer 10

0-6

Question 11

What are alkalis on the pH scale?

Answer 11

8-14

Question 12

What is neutral on the pH scale?

Answer 12

7

Question 13

What occurs when an acid and an alkali mix?

Answer 13

A neutralisation reacion

Question 14

Are all alkalis bases?

Answer 14

No. Alkalis are soluble bases

Question 15

What is a base?

Answer 15

Something that neutralises an acid

Question 16

Is a neutralisation reaction exothermic or endothermic?

Answer 16

Endothermic

Question 17

What does exothermic mean?

Answer 17

Takes in heat - cools down

Question 18

What does endothermic mean?

Answer 18

Gives off heat - warms up

Question 19

Finish the word equation:
Acid + Alkali/Base —>

Answer 19

a salt + water