# What are the coefficients needed to balance Pb(NO_3)_2 + NaI -> PbI_2 + NaNO_3?

Apr 5, 2016

$1 , 2 \to 1 , 2$

#### Explanation:

1.Make a list of elements present in the reactants and products.
2. Count the atoms in the reactants and products.
3. Place coefficients in front of molecules to balance the numbers of atoms. Continue till the reactants equal the products.

${_}_{_} P b {\left(N {O}_{3}\right)}_{2} {+}_{_} _ N a I {\to}_{_} _ P b {I}_{2} {+}_{_} _ N a N {O}_{3}$
1. Pb 1
2. N 1
6. O 3
1. Na 1
1. I 2

${_}_{_} P b {\left(N {O}_{3}\right)}_{2} + 2. N a I {\to}_{_} _ P b {I}_{2} + 2. N a N {O}_{3}$
1. Pb 1
2. N 2
6. O 6
2 Na 2
2 I 2

Here's a video with extra practice problems!