Question

Which pair of elements reacts most readily?
A. Li + br2
B. li + cl2
C. K + br2
D. K + cl2
Please explain the correct answer

Answer 1

Either A or B

I forgot reactions with Chlorination/Bromination.

But I think Bromination are faster and more specific......

Answer 2

D. K + Cl2

This is because for the alkali metals, reactivity increases as you go down the group (as the ionisation energy decreases), making K more reactive than Li. For halogens, electronegativity increases as you go up the group, making Cl2 more reactive than Br2.

Answer 3

K is the most reactive group 1 and CL is more reactive than Br so yes option D.