Question

Ammonia reacts with oxygen to produce nitrogen and water. The balanced chemical
equation for the reaction is 4NH3 + 3O2 --------> 2N2 + 6 H2O
how many grams of NH3 are needed to produce 2.65 g of water

Answer 1

Balanced Equation :

4NH3 + 3O2 --------> 2N2 + 6 H2O

Mass of water : 2.65 g

Molecular mass of water, M = 18 g/mol

Moles of water = 2.65/18 = 0.1472 moles

From ,the equation we can see that, 4 moles of NH3 reacts to form 6 moles of H2O

So,

Moles of  NH3 needed =  0.1472 * (4/6) = 0.09813 moles

Molecular mass of NH3 = 17 g/mol

Mass of NH3 needed = Molecular mass X no of moles

= 17 * 0.09813 = 1.668 g

Hence, 1.668 grams of NH3 are needed to produce 2.65 g of water.