Chemistry

posted by on .

Lithium nitride reacts with water to form ammonia and aqueous lithium hydroxide.

Li3N(s) + 3H2O(l) ==> NH3(g) + 3LiOH(aq)

a)What mass of water is needed to react with 32.9g Li3N?
b)When the above reaction takes place, how many molecules of NH3 are produced?
c)Calculate the number of grams of Li3N that must be added to an excess of water to produce 15.0L NH3(at STP).

• Chemistry - ,

1. Write and balance the equation. You have that.

a. Convert 32.9 g Li3N to moles. moles = grams/molar mass.
Using the coefficients in the balanced equation, convert moles Li3N to moles H2O.
Then convert moles H2O to grams. g = moles x molar mass.

b. To obtain moles NH3, use the same process as in part a. Then remember that 1 mole of any material contains 6.022 x 10^23 molecules.

c. Same procedure as in a except convert 15.0 L NH3 at STP (remember 1 mole of a gas occupies 22.4 L at STP) to moles, convert moles NH3 to moles Li3N, then grams = moles x molar mass.

Post your work if you get stuck.

• Chemistry - ,

For a I have .948 mol Li3N and for h20 I have 17.07848544 grams so now what do I do

• Chemistry - ,

I got answers for a and b but I don't know where to begin on c