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Hydrogen displacement

Can be displaced from an aqueous solutions
The solution is an acid

Metals above hydrogen in the reactivity series can displace hydrogen gas from dilute hydrochloric/ sulfuric acid

1

Displacement of metals from their salts

Any metal will displace another below it in the reactivity series from a solution of one of its salts

2

Salts of metals

Chlorides, nitrates, sulfates

3

Chlorides

Soluble on waer except silver chloride and led (iii) chloride

4

Nitrates

Soluble in water

5

Sulfates

Soluble in water
except barium sulfate, calcium sulfate and lead (ii) sulfate

6

Reduction

Oxygen removed from a metal oxide

7

Reducing agent

A substance that carries out the reduction

8

Reduction of a metal oxide

Heating the metal oxide with a more reactive metal

9

Carbon in reduction

Can reduce some metal oxides into metals
Carbon becomes carbon dioxide

10

Combustion of hydrogen

Hydrogen burns when heated in air or oxygen
Forms water

11

Test for hydrogen

Put a lighted splint at the mouth of a test tube, a squeaky pop will be heard if hydrogen is present

12

Test for water

Add the liquid to anhydrous copper (ii) sulfate
The white powder will turn blue if pure water is present
Copper (ii) sulfate formed

Boils at 100*C freezes at 0*C

13

Sacrificial protection of iron

Zinc is more reactive than iron
Even if the iron is scratched the iron is still protected because the zinc reacted and corrodes instead of the iron.

14

Galvanised iron

Iron coated in zinc

15

Preventing steel and iron rusting

Can be prevented by preventing contact with water and oxygen
Can be done by orating in: grease, oil, paint, plastic, a less reactive metal

16

Problems of coating to prevent rusting

Once the coating is scratched/washed away the iron is once again exposed to water and oxygen and will rust

17

Rusting of iron

Iron+ water+ oxygen

Iron ---> iron (iii) due to loss of electrons

18

Speeding up rusting

By having electrolytes in the water

19

More reactive the hydrogen metals

React with both: dilute hydrochloric acid and dilute sulfuric acid
Form a salt and hydrogen

20

magnesium+ HCl / H2SO4

Bubbles
Disappears
Mixture gets hot
Colourless solution formed

21

Aluminium+ HCl / H2SO4

Bubbles when heated
Disappears
Colourless
Solution formed

22

Zinc+ HCl / H2SO4

Bubbles
Disappears
Colourless solution formed

23

Iron+ HCl / H2SO4

Bubbles
Disappears
Pale green solution formed

24

Presence of carbon dioxide

Limewater turns milky

25

Carbon dioxide absorbs

infra red

26

Acid rain

Rain with a below 6 PH
leaches vital vitamin out of the soil- kills trees
Lowers the PH of lakes so that fish can't live in it
Weathers building made of; limestone, marble, iron

27

Laboratory preparation of carbon dioxide

Metal carbonate + an acid = carbon dioxide
Calcium carbonate most often used

28

Laboratory preparation of oxygen

Hydrogen peroxide decomposes slowly and forms water and oxygen

Decomposition sped up by adding the catalyst solid manganese dioxide

29

Finding oxygen using iron

Place wet iron fillings at the end of a burette
Water rises up the burette
Due to iron reacting with air

Percentage of oxygen =
( volume of oxygen used/volume of air at start ) x 100

30

Finding oxygen - copper

Aparratus with 100cm^3 of air
Heat copper at one end of the silica tube
Pass air over the copper
Keep heating fresh copper
Stop heating when gas in the servings stops decreasing
Final volume of air left should be 79cm^3
21cm^3 has reacted

31

Nitrogen in air

78%

32

Oxygen in air

21%

33

Argon in air

0.9%

34

Carbon in air

0.04%

35

Group 7

Halogens
Non-metals
Poisonous
React with metals and form salts

36

Three halogens

Chlorine
Bromine
Iodine

37

Chlorine room temperature

Gas
Green

38

Bromine room temperature

Liquid
Red-brown

39

Iodine room temperature

Solid
Black

40

Group number

Number of electrons in outer shell

41

Same group

Same chemical properties

42

Periodic group left to right

Increasing atomic number
Periods

43

Top to bottom

The more shells
Groups

44

Group 1

More reactive the further down you go
Very reactive metals
Stored under oil so they can't react with water/oxygen
Alkali metals
React with water form alkaline solutions

45

Group 1 characteristics

Good conductors
Very soft
Low melting/ boiling points
Low densities
Shiny surface (dull after reacting with oxygen)
Burnt in air/oxygen
Form white, solid oxides

46

Group 8/0

Noble gases
Chemically unreactive
Neither lose or gain electrons easily