Pb(NO3)2(aq) + KCl(aq) → KNO3(aq) + PbC12(s)

If you’re asking to balance the equation then:

Pb(NO3)2(aq) + 2KCl(aq) -> 2KNO3(aq) + PbCl2(s)

Just remember: the equations at the end is Cl not C12

Note: the small number on the bottom (subscripts) apply to the one element if it’s inside the bracket and if the small number is on the outside of the bracket it applies to all the elements. For example the 3 in (NO3)2 applied only to the O (oxygen) and the 2 applies to both N and O but don’t forget it’s multiplied. So it would be 2 N’s and 6 O’s bc the 3 multiplies with the 2 only for the O.

The air is going to come out because of the low pressure.