Balance Ca(NO3)2 + NaCl ---> NaNO3 + CaCl2

Ca(NO3)2 + 2 NaCl = 2 NaNO3 + CaCl2

Explanation:

On the left you have an original balance of Ca - 1, N - 2, O - 6, Na - 1, and Cl - 2, and on the right you have a balance of Ca - 1, N - 1, O - 3, Na - 1, Cl - 2.

Ca - 1 Ca - 1

N - 2 N - 1

O - 6 O - 3

Na - 1 Na - 1

Cl - 1 Cl - 2

In order to balance these, you'll have to make both sides equal. To get the N on the right to be equal to the N on the left, you'll have to multiply NaNO3 by 2, thus making it 2NaNO3. By doing this, you will offset the balance of both Na and O.

Ca - 1 Ca - 1

N - 2 N - 2

O - 6 O - 6

Na - 1 Na - 2

Cl - 1 Cl - 2

To balance the rest of the equation, you'll have to multiply both Na and Cl by 2. This will change NaCl to 2NaCl, making the balance look like this:

Ca - 1 Ca - 1

N - 2 N - 2

O - 6 O - 6

Na - 2 Na - 2

Cl - 2 Cl - 2

You will now be left with your final equation Ca(NO3)2 + 2 NaCl = 2 NaNO3 + CaCl2.