Atomic Structure
Bonding
Quantitative
Chemical Changes
Energy Changes
100
This group increases in density and boiling point as you move down.
What is group 1?
100
Bonding type held together by electrostatic forces.
Ionic bonding
100
No atoms are lost or made during a chemical reaction so the mass of the products equals the mass of the reactants
What is the law of conservation of mass?
100
Why does the electrolyte have to be molten or aqueous for electrolysis reactions?
Ions have to be able to move.
100
Takes in energy from the surroundings so the temperature of the surroundings decreases.
What is an Endotherminc reaction?
200
This atom has the same electron configuration as a caesium ion.
Who is Xenon?
200
Carbon nanotubes and graphene have this in common.
What is conducts electricity, hexagonal rings and each carbon atom making 3 C-C bonds?
200
Caffiene is a stimulant drug that when abused can cause heart problems, poor blood flow and symptoms of anxiety.
Calculate the Mr of Caffiene (C8H10N4O2)
194
200
What substances could react with nitric acid to produce calcium nitrate?
Calcium, calcium carbonate, calcium oxide, calcium carbonate.
200
Exothermic reaction
300
He suggested electrons orbit the nucleus at specific distances
How did Niels Bohr adapt the nuclear model of the atom?
300
Who has the higher boiling point:
Ethane or Butane.
Explain your answer
Butane.
Larger molecule has stronger intermolecular forces, which needs more energy to overcome.
300
Paracetamol is a common pain reliever.
How many moles of paracetamol are in 6g of paracetamol (C8H9NO2 )?
Ar: C = 12 H = 1 N = 14 O = 16
Mr of C8H9NO2 =151
6g / 151 = 0.0397 moles
300
3 steps that help ensure a fair and valid titration
1. White tile to easily see the indicator colour
2. Indicator to see the change in pH
3. Using a pipette for exact measurements.
300
2 Control variables for the Temperature Changes Practical.
1. Volume/concentration of alkali
2. Surrounding temperature.
400
Why won't Argon react to form compounds?
1. Stable electron configuration
2. Does not need to lose/gain/share electrons
400
Explain why buckministerfullerene is a good lubricant.
Sphere shape, easy to roll/move around each other.
400
How many atoms are in 3 moles of ethanoic acid? Give your answer in standard form.
3mol x 6.02 x 1023 = 1.806 x1024
400
HIGHER: Explain why we say copper is reduced at the cathode during the electrolysis of copper chloride.
Foundation: Explain why methane is oxidised when burned.
H: Copper (ions) gains electrons.
F: Methane/Carbon gains oxygen
400
Explain why the reaction between hydrogen and chlorine releases energy.
1. energy is needed to break bonds and energy is released when bonds form
2. the energy released is greater than the energy needed
500
Explain how the discovery of Gallium proved Mendeleevs periodic table to be correct?
1. Mendeleev left gaps where he thought undiscovered elements would fit based on atomic weight
2. Gallium fit that gap
3. Gallium matched Mendeleevs predicted properties.
500
What happens to magnesium and bromine atoms when they react to form magnesium bromide?
1. Magnesium loses 2 electrons
2. Magnesium forms a 2+ ion
3. 2 bromine atoms gains 1 electron
4. Bromine forms a 1- ion
500
Metal X is extracted by a reaction with hydrogen.
XO3 + 3 H2 → X + 3 H2O
The percentage atom economy for obtaining metal X by this method is 77.3%.
Calculate the relative atomic mass of metal X.
Ar: H = 1 O = 16
(ArX / (ArX + 54)) x 100% = 77.3%
ArX = (ArX + 54) x 0.773
0.227ArX = 41.742
ArX = 184
500
During the Making Salts Practical, why:
1. Is the acid warmed
2. Is the solution filtered
1. To increase the rate/speed of the reaction
2. To remove the excess base
500
Explain the trend on this graph of hydrochloric acid being added to sodium hydroxide.
Energy increased until 300 seconds
Because the reaction had finished/all of the sodium hydroxide reacted.