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

Mass = 51.12 g

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

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the average time it took the car to travel 0.50 meters was 2.61 seconds

hope this : )

it is the most commonly accepted one