In the change represented by the equation co2(s) to co2(g) the co2(s) is

represent solid form of carbon-dioxide gas in the reaction.

Explanation:

In the given reaction solid phase of carbon-dioxide is changing directly into gaseous phase of carbon-dioxide. This process of changing of substance from solid to gaseous state directly by escaping the liquid state is known as Sublimation.

Here is representing the solid state of carbon-dioxide which is also known as Dry-ice.

answer: -

reaction:

na + cl ⇌ nacl

balanced chemical equation:

na + 2cl ⇌ nacl2

sodium + clorine goes to form sodium chloride (table salt).

the product is nacl2.

and the reactants are na and cl.

(note: if you don’t know what ⇌ means, read below: -

⇌(double head arrow) means reversible reaction).

i'm pretty sure its b i might be wrong though!