9 23 When heated with chlorine, the hydrocarbon 2,2-dimethylbutane undergoes free radical
substitution.
In a propagation step a free radical X. is formed.
CH3
CH, CH, -C-CH3 + Cl• → X• + HCI
N
CHE
How many different structures of X• are possible?
A 2
B 3
C 4
D 5

the only liquid elements at standard temperature and pressure are bromine (br) and mercury (hg). although, elements caesium (cs), rubidium (rb), francium (fr) and gallium (ga) become liquid at or just above room temperature.

explanation:

it's c (engineer's do their work with mechanical stuff not on any living being)