The following reaction: H2 + I2 → 2HI, is an example of

a) synthesis.
b) decomposition.
c) single-displacement.
d) double-displacement.

The following reaction: H2 + I2 → 2HI, is an example of  synthesis reaction

Explanation:

Synthesis reaction:

relative humidity is a measure of the amount of moisture in the air relative to the total amount of moisture the air can hold.

so d

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: