chemical reactions - acids and alkalis

Question 1

wha are the three main types of acid used in chemistry

Answer 1

hydrochloric acid
sulphuric acid
nitric acid

Question 2

what do acids produce in aqueous solutions

Answer 2

hydrogen ions (H+)

Question 3

what are bases

Answer 3

chemicals which can neutralize acids producing a salt and water

Question 4

give some examples of a base

Answer 4

metal oxides, or metal hydroxides

Question 5

what are alkalis

Answer 5

bases which are soluble with water

Question 6

name an example of an alkali often used in chemistry

Answer 6

sodium hydroxide

Question 7

what do alkalis produce in aqueous solutions

Answer 7

hydroxide ions (OH-)

Question 8

what does the ph scale tell us

Answer 8

the acidity or alkalinity of a solution

Question 9

what ph do acids have

Answer 9

a ph between 0-6

Question 10

if a solution has a ph of 7 it is…

Answer 10

neutral

Question 11

what ph do alkalis have

Answer 11

a ph between 8-14

Question 12

how can you determine the ph of a solution

Answer 12

a ph probe - electronically
or
universal indicator - changes color

Question 13

for universal indicators what do each of these colors tell us about the solution
green, red, purple

Answer 13

green - neutral
red - acids
purple - alkaline

Question 14

what is the equation for neutralization

Answer 14

H+ + OH- ——-> H2O

Question 15

what do alll acids contain

Answer 15

hydrogen

Question 16

what does sulfuric acid produce

Answer 16

salts called sulphates

Question 17

what does hydrochloric acid produce

Answer 17

salts called chlorides

Question 18

what does nitric acid produce

Answer 18

salts called nitrates

Question 19

metal + ____ —–> ____ + hydrogen

Answer 19

metal + acid ——> salt + hydrogen

Question 20

what happens when you react an acid with a base or alkali

Answer 20

we make a salt + water

Question 21

when an acids react with a metal carbonate what is made

Answer 21

salt, water, carbon dioxide

Question 22

what do all salts contain

Answer 22

a positive ion which is the metal ion

Question 23

for the salt copper sulfate, list all the different ways we could achieve the positive ion

Answer 23

• metal itself, copper
• metal oxide, copper oxide
• metal hydroxide, copper hydroxide
• metal carbonate, copper carbonate

Question 24

what color is copper oxide

Answer 24

black

Question 25

what equipment is used for this practical

Answer 25

heatproof mat, bunsen burner, tripod, gauze, beaker

Question 26

talk about the required practical of making a soluble salt

Answer 26

1. pour your fixed volume of dilute sulphuric acid into your beaker - this is the limiting reactant
2. gently heat the acid until most boiling - don’t boil as it could over spill
3. use a spatula to add a small amount of copper oxide
4. stir using a glass rod
5. the copper oxide will react and ‘disappear’ - it will turn blue
6. add until there is excess copper oxide - all of the acid has been used up
7. filter top remove excess copper oxide
8. take solution and place in an evaporating dish
9. heat gently until half solution remains
10. leave to evaporate and collect copper sulphate crystals