Write chemical equation to show the reaction between sodium and oxygen gas .calculate the mass of the product formed when 11.5 sodium reacted completely (relative atomic mass, oxygen=16,sodium=23

1. 4Na + O2 —> 2Na2O

2. 15.5g

Explanation:

1. The reaction between sodium (Na) and oxygen gas (O2) produced sodium oxide (Na2O). This is illustrated below:

Na + O2 —> Na2O

The equation can be balance as follows:

There are 2 atoms of O on the left side of the equation and 1atom on the right side. It can be balance by putting 2 in front of Na2O as shown below:

Na + O2 —> 2Na2O

Now, we have 4 atoms of Na on the right side and 1atom on the left side. It can be balance by putting 4 in front of Na as shown below:

4Na + O2 —> 2Na2O

Now the equation is balanced.

2. To obtain the mass of the product formed from 11.5g of sodium (Na), first, let us obtain the masses formed from the balanced equation. This is illustrated below:

4Na + O2 —> 2Na2O

Molar Mass of Na = 23g/mol

Mass of Na from the balanced equation = 4 x 23 = 92g

Molar Mass of of Na2O = (23x2) + 16 = 46 + 16 = 62g/mol

Mass of Na2O from the balanced equation = 2 x 62 = 124g

From the balanced equation,

92g of Na produced 124g of Na2O.

Therefore, 11.5g of Na will produce = (11.5 x 124)/92 = 15.5g of Na2O

Therefore, 15.5g of the product (Na2O) are produced