3. When magnesium oxide reacts with dilute sulfuric acid the equation is
MgO(s) + H2SO4(aq) → MgSO4(aq) + H2O(l)
What is the ionic equation for the reaction?
A MgO(s) + 2H+(aq) + SO42−(aq) → Mg2+(aq) + SO42−(aq) + H2O(l)
B MgO(s) + 2H+(aq) → Mg2+(aq) + H2O(l)
C Mg2+(s) + SO42−(aq) → Mg2+(aq) + SO42−(aq)
D O2−(s) + 2H+(aq) → H2O(l)
ANSWER
B MgO(s) + 2H+(aq) → Mg2+(aq) + H2O(l)
Analysis of Option/Explanation
Remember for ionic equation, we only ionize aqueous part and the other i.e. in solid and liquid state is written as it is.
MgO(s) + H2SO4(aq) → MgSO4(aq) + H2O(l)
MgO(s) +2H+ + SO42- →Mg2+ + SO42- + H2O(l)
Cancel those which are on both sides of equation
MgO(s) +2H+ + SO42- →Mg2+ + SO42- + H2O(l)
MgO(s) +2H+→ Mg2+ H2O(l)
Hence, Option B is the correct answer.
