Chem

Question 1

Water displacement

Answer 1

Hydrogen , oxygen, carbon dioxide

Question 2

Methods of drying gas

Answer 2

Concentrated sulfuric acid
- most gases
- not ammonia

Quicklime - calcium oxide
- ammonia
- not acidic gases eg co2

Fused calcium chloride
- hydrogen, nitrogen, carbon dioxide
- not ammonia

Question 3

Methods for seperating sol sol

Answer 3

Magnetic
Sieving
Suitable solvents
Sublimation

Question 4

Seperating sol-liq mixtures

Answer 4

Filtration
- filter funnel filter paper
Evaporation

Crystallisation
- heat until saturated
- cool , wash, dry

Simple distillation
- solvent boils and vapourises
- enters condenser , cools and condense
- solvent collected in liquid form

Question 5

Seperating sol-liq mixtures

Answer 5

Filtration
- filter funnel filter paper
Evaporation

Crystallisation
- heat until saturated
- cool , wash, dry

Simple distillation
- solvent boils and vapourises
- enters condenser , cools and condense
- solvent collected in liquid form

Question 6

Miscible
Vs
Immiscible

Answer 6

Liq which form a homogeneous solution when mixed tgt

Liq which form heterogenous mixture —> can separate by density

Question 7

Separating liq-liq

Answer 7

Separating funnel
Chromatography
- identify substances in food
- detect banned substances in athletes urine
- separate components like DMA fragments

Fractional distillation
- both liq will vapourise
- the one w higher boiling point condense on fractionating column first, returns to flask
- liq w lower bp condenses

Question 8

Nuclide notation

Answer 8

Nucleon number on top (tot mass)

Proton number below

Question 9

Isotopes

Answer 9

Atoms of same element w same proton num diff neutron num

Question 10

Alloys

Answer 10

Different sized atoms disrupt orderly arrangement, layers hard to slide over each other when force applied, harder to break

Question 11

Macromolecules

Answer 11

Large molecule made of many small molecules joined tgt