Question

What mass of water is needed to react with 32.9 g lithium nitride

Answer 1

Mass = 51.12 g

Step-by-step explanation:

Given data:

Mass of lithium nitride = 32.9 g

Mass of water needed = ?

Solution:

Chemical equation:

Li₃N + 3H₂O → NH₃ + 3LiOH

Number of moles of lithium nitride:

Number of moles = mass/ molar mass

Number of moles = 32.9 g/ 34.83 g/mol

Number of moles = 0.945 mol

Now we will compare the moles of water and lithium nitride.

Li₃N : H₂O

1 : 3

0.945 : 3×0.945 = 2.84 mol

Mass of water:

Mass = number of moles × molar mass

Mass = 2.84 mol × 18 g/mol

Mass = 51.12 g