Help pl When heated, lithium reacts with nitrogen to form lithium nitride:

Li(s) + N2(g) > Li3N(s)

What is the theoretical yield of Li3N in grams when 12.3 g of Li are heated with 33.6 g of N2?

If the actual yield of Li3N is 5.89 g, what is the percent yield of the reaction?

Percent yield =28.7%

Theoretical yield  = 20.55 g

Explanation:

Given data:

Mass of Li₃N = ?

Mass of Li = 12.3 g

Mass of N₂ = 33.6 g

Actual yield = 5.89 g

Percent yield = ?

Solution:

Chemical equation:

6Li + N₂     →       2Li₃N

Number of moles of Li:

Number of moles = mass/molar mass

Number of moles = 12.3 g / 6.9 g/mol

Number of moles = 1.78 mol

Number of moles of N₂:

Number of moles = mass/molar mass

Number of moles = 33.6 g / 28 g/mol

Number of moles = 1.2 mol

Now we will compare the moles of both reactant with product.

                 N₂         :         Li₃N

                  1           :           2

                1.2          :       2/1×1.2 = 2.4 mol

                Li           :         Li₃N

                 6           :           2

                1.78        :       2/6×1.78 =  0.59 mol

Less number of moles of Li₃N are produced by Li thus it will be act as limiting reactant.

Mass of Li₃N: Theoretical yield

Mass = number of moles × molar mass

Mass = 0.59 mol × 34.83 g/mol

Mass = 20.55 g

Percent yield:

Percent yield = ( Actual yield / theoretical yield ) × 100

Percent yield =  ( 5.89 g/ 20.55 g) × 100

Percent yield =28.7%

conduction is the transfer of thermal energy (heat in transfer) due to collisions between the molecules in the object. collisions between adjacent atoms and molecules transfer kinetic energy from the warmer to the cooler object. the objects must be in physical contact.