# How would you balance H2 + O2 = H2O?

##### 2 Answers

2H2 + O2 = 2H2O

#### Explanation:

From the original equation, you first need to write each component separately.

Left side: H = **2** ; O = **2** (number based on the subscript)

Right side: H = **2** ; O = **1** (number based on the subscripts; no subscript means that the element is just 1)

Notice that the number of H is already balance but the number of O is not. In order to balance the O, you need to multiply the element by 2, but you CANNOT do this by simply changing the subscript.

Hence,

Left side: H = **2** ; O = **2**

Right side: H = 2 x 2 = **4** ; O = 1 x 2 = **2**

Now, notice that the number of O is now balance (both are 2) but the number of H is not (since

You also multiply the left side H by 2. Hence,

Left side: H = 2 x 2 = **4** ; O = **2**

Right side: H = 2 x 2 = **4** ; O = 1 x 2 = **2**

The equation is now balanced.