Group 7 Flashcards
What are group 7 ions known as (atomic)
diatomic molecule - since they travel as 2
What are Gp7 elements like at room temperature
F2 - yellow gas
Cl2 - green gas
Br2 - orange liquid
I2 - grey solid
what is the trend in melting point as you descend Gp7
Melting point increases as molecules get bigger
How do halogens react with metals
they gain 1 electron
how do displacement reactions work in Gp7
you use a halide salt which is colourless in solution
and add a coloured halogen
if solution gets darker a reaction has occured
what do results show from a displacement test in Gp7
Cl > Br > I - it gives an order of reactivity because the chlorine displaced both Br- and I- from the metal
Why are elements less reactive further down Gp7
the electron gained is further from the nucleus
more shielded by the full shells between the nucleus
less strongly attached
so electron is gained LESS easily
