Answer:
MgO + H₂
Explanation:
The products of reaction is MgO and hydrogen gas.
This is a single displacement reaction.
In this reaction, the possibility of the reaction is determined by position of the atoms on the activity series.
Mg is higher than H on the activity series, so it is more reactive and it then displaces the hydrogen in water;
Mg + H₂O → MgO + H₂
Answer:
0.250 moles of MgO are produced when 0.250 mol of Mg reacts completely with O₂
Explanation:
In first place, the balanced reaction between Mg and O₂ is:
2 Mg + O₂ ⇒ 2 MgO
By stoichiometry of the reaction (that is, the relationship between the amount of reagents and products in a chemical reaction), the following amounts of reactants and products participate in the reaction:
- Mg: 2 moles
- O₂: 1 mole
- MgO: 2 moles
Then you can apply the following rule of three: if by reaction stoichiometry 2 moles of Mg produce 2 moles of MgO, 0.250 moles of Mg, how many moles of MgO will they form?

moles of MgO= 0.250
<u><em>0.250 moles of MgO are produced when 0.250 mol of Mg reacts completely with O₂</em></u>
It is the mass of one mole of the substance.