Answer:

Explanation:
<u>Synthesis reaction:</u>
In the synthesis reaction, two reactants combined to form a single product.
For example,
"A" and "B" are two reactants then combined to form a "AB" product.
The chemical reaction is as follows.

The product "MgO" is formed by magnesium reacts with oxygen to form Magnesium oxide.
The chemical reaction is as follows.

Answer:
Rubidium Sulfide
Explanation:
The chemical name for Rb2S is Rubidium Sulfide
H2SO4 (1) H20 (g) + SO3 (g)
The answer is D. element
It's not a mixture, just a pure element. Copper (Cu) is found on the Periodic Table of the Elements, where only ELEMENTS are organized.