T4 - Inorganic chemistry Flashcards
What is the positive flame test for lithium?
Crimson red
What is the positive flame test for sodium?
Yellow - orange
What is the positive flame test for potassium?
Lilac
What is the positive flame test for rubidium?
Red/purple
What is the positive flame test for caesium?
Blue/violet
What is the positive flame test for beryllium?
N/A
What is the positive flame test for magnesium?
N/A
What is the positive flame test for calcium?
Brick red
What is the positive flame test for strontium?
Crimson red
What is the positive flame test for barium?
Apple green
Define thermal decomposition
The breaking down of a substance using heat energy
What is produced when carbonates decompose? (Give equation)
Metal oxide and carbon dioxide
G1 - M2CO3 —> M2O + CO2
G2 - MCO3 —> MO + CO2
What is an acid?
Hydrogen ion donor
What is a base?
Hydrogen ion accepting
What is an alkali?
A base that dissolves in water
What is the trend in solubility down group 2 hydroxides?
The solubility increases down the group
What is the trend in solubility down group 2 sulfates?
The solubility decreases down a group
Trends in ionisation energy down group 2 and explain why.
Ionisation energy decreases down the group
Size - Atomic radius increases so the electron is further away from the nucleus so is less attracted by the positive nucleus
Nuclear charge - Number of protons increase so there’s a greater attraction to outer electrons (This factor is outweighed)
Shielding - There is an extra shell of electrons for each element downwards, which increases shielding, decreasing the attraction to the outer electron
What is the colour of pure elemental chlorine?
Green gas
What is the colour of chlorine dissolved in water?
Pale green
What is the colour of chlorine dissolved in cyclohexane?
Pale green
What is the colour of pure elemental bromine?
Red-brown liquid
What is the colour of bromine dissolved in water?
Orange
What is the colour of bromine dissolved in cyclohexane?
Darker orange
What is the colour of pure elemental iodine?
Grey/silver solid or a purple gas
What is the colour of iodine dissolved in water?
BrownW
What is the colour of iodine dissolved in cyclohexane?
Purple
Which halogen and group 1 metal will give the most vigorous reaction?
F and Fr
When a halogen and metal react, which is the oxidising agent and which is the reducing agent?
Halogen is the oxidising agent
Metal is the reducing agent
What is the trend in electronegativity in group 7 and explain why?
Decreases down a group
- S: Has a larger atomic radius, so electrons are further away
- N: More protons, larger nuclear charge = more attraction
- S: Greater sheilding = less attraction
What is the method for halogen displacement practical?
- Add halide to halogen in solution
- Add organic solvent (cyclohexane)
- Gently shake and allow to settle
- Observe layers and colour changes
In the halogen displacement practical, why does the cyclohexane layer sit on top?
The water layer is more dense than the cyclohexane
Why is an organic solvent added in the halogen displacement practical?
As the displaced halogen and organic solvent are both non-polar, so they interact better and have better london forces between them.
