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Topic 1: Properties & structure of atoms
Topic 2: Properties & structure of materials
Topic 3: Chemical reactions - reactants, products and energy change
Unit 2. Topic 1: Intermolecular forces and gases
Misc
100

The number of electrons in the p sublevel.

6

100

Distinguish elements and compounds.

Elements contain only one type of atom, but compounds are made of two or more different atoms that are chemically joined.

100

A chemical reaction in which energy is absorbed from the surroundings.

Endothermic.

100

The strongest of the intermolecular forces.

Hydrogen bonding.

100
Group 18 elements (last on the table) are called:
The Noble Gases
200

The distinguishing feature of isotopes.

Number of neutrons.

200

The type of bonding that allows electrical conductivity when molten or in solution, but not as a solid.

Ionic bonding

200

The amount of energy needed to heat 1500g of water from 20oC to 90oC.

438900J or 4.389 kJ.

200

The structure of ammonia (using VSEPR theory).

Trigonal pyramidal

200

Explain the difference between 'strong' and 'concentrated'

Strong - completely ionises/dissociates in water. e.g. HCl (Can be concentrated or diluted.)

Concentrated - There are a lot of molecules (or ions) in solution.

300

Chlorine-35 has an abundance of 75.77%. 

Chlorine-37 has an abundance of 24.23%.

Calculate its relative atomic mass.

((35x75.77) +(37x24.23))/100 = 35.48 amu

300

The difference between a homogeneous and a heterogeneous mixture.

A homogeneous mixture appears uniform, but a heterogeneous mixture does not.

300
Draw an enthalpy diagram for an exothermic reaction.

Products need to have lower energy than reactants. Show activation energy.

300

Explain the difference between the boiling points of chlorine and iodine.

Both are group 17 elements. Iodine is larger; has more electrons, so has increased dispersion forces.
300

The name given to the vertical columns on the periodic table.

Groups

400

Write a full electron configuration for potassium

1s2 2s2 2p6 3s2 3p6 4s1

400

Explain the electrical conductivity of metals.

Electrons in metallic substances are able to move, and do so when an electrical current is applied.

400

The number of moles in 100g of water.

n=m/M

 = 100/18.02

 = 5.55

400

Explain the relationship between the pressure and volume of a gas, at constant temperature.

As pressure increases, volume decreases.

400
Atoms from different elements have a different number of _________________ in the nucleus.
Protons
500

Draw an orbital diagram for chlorine.

Up, down (1s), up, down (2s), UD UD UD (2p), UD (3s) UD UD U (3p)

500

Explain similarities and differences between physical properties of covalent molecular and covalent network substances.

Similarities - No electrical conductivity (except graphite)

Differences - Cov. network substances are harder and have higher melting and boiling points than covalent molecular bonded substances.

500

Carbon dioxide is formed in a chemical reaction. Calculate the enthalpy for the bonds formed.

O=C=O

2 x 804 = 1608 kJ/mol

500

3 moles of a gas is in a container at STP. What volume does the gas occupy?

PV = nRT

V = 3 x 8.31 x 273/100 = 68.1L

500

Atoms with an overall positive charge are called:

Cations