chemical tests

Question 1

test for ammonia

Answer 1

damps red litmus paper turns blue

Question 2

carbon dioxide test

Answer 2

bubble through limewater, it turns milky/cloudy

Question 3

chlorine test

Answer 3

Damp blue litmus paper it bleaches white

Question 4

hydrogen test

Answer 4

hold a lighted splint in mouth of test tube, burns with a ‘squeaky pop’ sound

Question 5

Oxygen

Answer 5

Hold a glowing splint, splint relights

Question 6

test for lithium

Answer 6

burns red

Question 7

sodium

Answer 7

burns yellow

Question 8

potassium

Answer 8

burns lilac

Question 9

calcium

Answer 9

burns Orange - red

Question 10

Copper

Answer 10

Burns Blue - green

Question 11

tet for ammonium

Answer 11

if its in hydroxide, ammonia gas produced damp red litmus blue

Question 12

test for Copper (II)

Answer 12

hydroxide test, light blue precipitate formed.

Question 13

Iron (II) test

Answer 13

hydroxide test, green precipitate formed.

Question 14

test for Iron (III)

Answer 14

hydroxide test, Red-brown precipitate formed

Question 15

test for carbonate

Answer 15

add dilute acid and test the gas realised, effervescence, gas produced is CO2 which turns limewater milky.

Question 16

test for chloride

Answer 16

add dilute nitric acid and add silver nitrate, white precipitate formed

Question 17

test for bromide

Answer 17

acidify with dilute nitric acid and add aqueous silver nitrate, cream precipitate formed.

Question 18

test for Iodide

Answer 18

add dilute nitric acid and add aqueous silver nitrate, yellow precipitate formed.

Question 19

test for sulfate

Answer 19

add dilute nitric acid and add aqueous barium nitrate, white precipitate formed.

Question 20

chemical test for water

Answer 20

Anhydrous copper (II) sulfate turns form white to blue on the addition of water

Question 21

equation for chemical test for water

Answer 21

CuSO4 (s) + 5H20 –> CuSO4.5HsO (s)

Question 22

Hydrogen Mr

Answer 22

(2x1) = 2

Question 23

water Mr

Answer 23

(2x1) + 16 + 18

Question 24

potassium Carbonate Mr

Answer 24

138

Question 25

calcium Hydroxide Mr

Answer 25

74

Question 26

ammonium sulfate Mr

Answer 26

132

Question 27

what is a mole

Answer 27

the number of atoms, molecules or ions in a mole of a given substacne is the Avogadro contsnt.

Question 28

how can you measure mole in a mass

Answer 28

the mass number of the atom is the weight in grams of one hole mole of atoms.

Question 29

what is the number for moles

Answer 29

6.02x10 to the 23

Question 30

mass in a mole-mass calculation

Answer 30

mass = moles x Mr

Question 31

mole in mole-mass calc

Answer 31

moles = mass/Mr

Question 32

what is the mass of 0.25 moles of zinc

Answer 32

16.25

Question 33

first step of calculating reacting masses

Answer 33

moles = mass/Mr

Question 34

step 2 of calculating reacting masses

Answer 34

find the ratio of Mg to MgO using the molar ratio form the balanced equation

Question 35

step 3 of calculating reacting masses

Answer 35

calculate the mass of MgO