One mole of a metallic oxide reacts with one mole of hydrogen to produce two moles of the pure metal and one mole of water. 5.00 g of the metallic oxide produces 2.32 g of the metal. What is the metallic
oxide? (Use molar masses)

Lithium oxide, Li₂O.  

Explanation:

Hello!  

In this case, according to the given amounts, it is possible to write down the chemical reaction as shown below:

Which means that the metallic oxide has the following formula: M₂O. Next, we can set up the following proportional factors according to the chemical reaction:

Thus, we perform the operations in order to obtain:

So we solve for x as shown below:

Whose molar mass corresponds to lithium, and therefore, the metallic oxide is lithium oxide, Li₂O.  

Best regards!

- "the choice that is not an indicator of a chemical change is "state of matter changes". more common than not, chemical reactions produce energy in the form of light or heat. along with energy, they also produce a new substance called the product that could be in any state of matter (solid, gas, or liquid)."

answer is: c. the experiment shows that the red substance experienced a chemical change.

this is chemical change (chemical reaction), because two new substances are formed (metalig liquid and gas), the atoms are rearranged and the reaction is followed by an energy change.

this is example of chemical decomposition.

chemical decomposition (analysis) is the separation of a single chemical compound into its two or more elemental parts or to simpler compounds.  

chemical decomposition is opposite of chemical synthesis.