Chemistry UA1

States of matter/ Diffusion /Water

Physical Properties of Liquids include:

• Flow and take the shape of the container.

• Do not have a definite volume

Physical Properties of Solids:

• Have a definite shape.

• Do not flow.

Physical Properties of a Gas:

• Do not have a definite volume

• Can flow

Sublimation

Solid → Gas

Deposition

Gas → Solid

Cooling Curve

Red Line A and Red Line B represent:

Red Line A : Boiling point

Red Line B : Melting Point

Heating Curve

Red Line A and Red Line B represent:

Red Line A: Melting Point

Red Line B: Boiling Point

What is Diffusion?

the net movement of particles from an area of higher concentration to an area of lower concentration

Diffusion can only occur in:

gases and liquids

Relative Molecular Mass:

Mr=(atomic mass x no. of atoms)

How does molecular mass affect the rate of diffusion?

The larger the molecular mass the slower the rate of diffusion. In contrast, the smaller the molecular mass the lighter the particles meaning t will move faster therefore a faster rate of diffusion.

What are the two main tests for the presence of Water?

1. Anhydrous cobalt (ii) chloride

2. Anhydrous copper (ii) sulphate

How do you tell if there is water present when using Anhydrous Copper (ii) Sulfate?

Turns from White to Blue meaning it is now hydrated.

How do you tell if water is present in Anhydrous Cobalt (ii) Chloride ?

Turns from Blue to Pink meaning it is now hydrated.

If the boiling point of water is below or above 100C what does it mean?

It has impurities

Natural sources found in water:

• Harmful Microbes

• Calcium, fluoride and magnesium ions

• Dissolved oxygen

• Nitrates from fertilisers

• Phosphates from fertilizers and detergents

Beneficiary substances in water:

• Dissolved Oxygen - essential for aquatic life’s respiration

• Iron, copper and zinc - essential micronutrients to life in the right concentrations

Harmful substance in water:

• Mercury and Lead - are toxic heavy metals

• Pastics

• Microbes cause diseases like cholera and typhoid

How do nitrates and phosphates lead to deoxygenation of water and damage aquatic life?

Nitrates and phosphates lead to the increase of growth of algae. The algae grows above the surface of the water. This blocks the light from the sun from reaching other plants like seaweed and will start to decompose. The decomposition of plants will lead to an increase in bacteria which during respiration use a lot of the oxygen leaving the fish to suffocate.

Process of domestic treatment to water supply