Aheating curve has two flat lines, or plateaus. what does the plateau at the higher temperature represent?
1. boiling of a liquid
2. melting of a solid
3. increase in temperature of a substance
4. decrease of a substance

The answer is B, the Melting point of a solid.

This is because it is a heating curve so the temperature is going to rise over time. The two plateaus mean that the element is changing phases and therefore the first plateau is the melting point because it goes from cold to hot.

Explanation:

Melting of a Solid

melting of a solid

Explanation:

...

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).