C4 Flashcards
How can you test for hydrogen?
Hydrogen will make a squeaky pop sound when exposed to a lit splint
What is the reaction between a group 1 element and oxygen?
Metal + oxygen -> metal oxide
State ad colour of bromine at room temp
Red-brown liquid
Physical state of group 0 elements
Gases
How can you test for oxygen?
Oxygen will relight a glowing splint
When performing the sodium hydroxide tests for metal ions, what is the colour of iron 2+ precipitate?
Green
What colour will sodium ions burn with ?
Yellow flame
Why are noble gases inert?
They already have a full outer-shell of electrons, so don’t need to gain or lose any electrons
Why should the wire be clean for a flame test?
So there are no impurities which could alter the colour of the flame
What colour will calcium ions burn with?
Orange-red flame
What colour will potassium ions burn with?
Lilac
When performing the sodium hydroxide test for metal ions, what is the colour of the copper precipitate?
Blue
Why do halogens become less reactive as you move down group 7 of the periodic table?
As you go down the group, atomic radius and shielding increase (which outweighs the increased nuclear charge).
This means there is a weaker electrostatic attraction between the nucleus and the electron it is trying to gain.
This means more energy is required for a reaction to occur.
When testing for halides, what colour precipitate does bromide form?
Bromide ions form a cream precipitate.
Why do alkali metals become more reactive down the group?
As you go down the group, atomic radius and shielding increase (which outweighs the increased nuclear charge).
This means there is a weaker electrostatic attraction between the outer-most electrons and the nucleus.
The means that the amount of energy required to lose the outer-most electron decreases, which makes it easier for a reaction to occur.
State the 3 trends seen in group 1 metals as you go down the periodic table.
Increased reactivity.
Lower melting and boiling points.
Higher atomic mass
What colour will copper ions burn with?
Copper ions burn with a green flame.
What are the properties of group 1 metals?
Soft.
Low density.
Very reactive.
Weak.
Relatively low melting points (compared to other metals).