# How would you balance Na2B4O7 + H2SO4 + H2O --> H3BO3 + Na2SO4?

##### 2 Answers

#### Explanation:

You first balance the metals, namely Sodium (

Next you do the non-metals, starting with anything but Oxygen (

Next is Boron (

The you balance the Hydrogen (

So you add a 5 to the water molecule on the left such that it doesn't effect the Sulphate ion, and in doing so balances the amount of Hydrogens (12 each side).

Everything should now balance, including Oxygen (16 on left and 16 on the right), if it doesn't, just keep trying by putting different values of coefficients before each molecule until it works out.

Remember that the coefficients should be the lowest value possible, and must not be fractions.

Hope I helped :)

#### Explanation:

It does not matter how long the equation is. You need to always start with tallying the number of atoms (based on the subscripts).

Left side:

Na = 2

B = 4

O = 7 + 4 + 1 (DO NOT ADD IT UP YET)

H = 2 + 2 (DO NOT ADD IT UP YET)

S= 1

Right side:

Na = 2

B = 1

O = 3 + 4 (DO NOT ADD IT UP YET)

H = 3

S= 1

Start with the element easiest to balance, in this case boron (B). Since B is part of the substance

Left side:

Na = 2

B = **4**

O = 7 + 4 + 1

H = 2 + 2

S= 1

Right side:

Na = 2

B = 1 x 4 = **4**

O = (3 x 4) + 4

H = (3 x 4) = 12

S= 1

Now, the number of H on your right side is 12. There are two H atoms on your left side that you can choose to multiply by 5 (since both values are 2) to balance. Choose the least complicated substance or the one with least number of other atoms attached to it. In this case, it is

Left side:

Na = 2

B = **4**

O = 7 + 4 + (1 x 5)

H = 2 + (2 x 5) = **12**

S= 1

Right side:

Na = 2

B = 1 x 4 = **4**

O = (3 x 4) + 4

H = (3 x 4) = **12**

S= 1

Now, look at your tally sheet and see it everything is balanced out.

Left side:

Na = **2**

B = **4**

O = 7 + 4 + (1 x 5) = **16**

H = 2 + (2 x 5) = **12**

S= 1

Right side:

Na = **2**

B = 1 x 4 = **4**

O = (3 x 4) + 4 = **16**

H = (3 x 4) = **12**

S= **1**

The equation is now balanced.