Question

Which net ionic equation describes this reaction? Mg(NO3)2(aq) + Na 2CO3(aq) → MgCO3(s) + 2NaNO 3(aq)

a) 2NO3–( aq) + 2Na+(aq) → 2NaNO3(aq)
b) 2NO3–(aq) + 2 Na+(aq) → 2NaNO3(aq) + 2NO3–(aq) + 2Na+(aq)
c) Mg2+(aq) + CO32–(aq) → MgCO3(s)
d) Mg2+(aq) + CO32–(aq) + 2NO3–(aq) + 2Na+(aq) → MgCO3(s)

Answer 1

To get the net ionic equations, the ions in the equation have to expressed into their ionic form
Mg2+ + 2NO3- + 2Na+ + CO32- -> MgCO3(s) + 2Na+ + 2NO3-
Cancel out the spectator ions (present in both sides of the reaction)
The result is
c) Mg2+(aq) + CO32–(aq) → MgCO3(s)