Step 1
The reaction must be written, completed, and balanced:
Pb(NO3)2 (aq) + H2SO4 (aq) => PbSO4 (s) + 2 HNO3 (aq) (completed and balanced)
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Step 2
The aqueous solutions will separate into ions, the solid won't.
Pb(NO3)2 (aq) + H2SO4 (aq) => PbSO4 (s) + 2 HNO3 (aq)
Pb+2 (aq) + 2 NO3-1 (aq) + 2 H+ (aq) + SO4-2 (aq) => PbSO4 (s) + 2 H+ (aq) + 2 NO3-1 (aq)
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Step 3
Same ions from different sides must be canceled as follows:
Answer: Pb+2 (aq) + SO4-2 (aq) => PbSO4 (s)