Question

The reaction below shows the decomposition of sodium azide into sodium metal and nitrogen gas.

Answer 1

Answer:

0.51g

Explanation:

Given parameters:

Volume of nitrogen gas  = 744mL

Unknown:

Mass of sodium metal produced = ?

Solution:

Let us assume that the gas, nitrogen was collected at STP which is the standard temperature and pressure, we can easily find its number of moles.

            Number of moles  = $\frac{volume of gas}{22.4}$

since the gas volume given is 744mL = 0.744mL

   Therefore input the variables;  

         Number of moles  = $\frac{0.744}{22.4}$   = 0.03moles

Now that we know the number of moles of the gas, let us revisit the reaction equation:

      2NaN₃   →   2Na    +  3N₂

It good to ensure that the reaction is balanced;

         3 mole of nitrogen gas is produced with 2 moles of Na

        0.03 mole of nitrogen gas will be produce with $\frac{0.03 x 2}{3}$  = 0.02mole

So;

       Using;

                    mass  = number of moles x molar mass

let us solve for the mass of Na;

                   molar mass of Na = 23g/mol

                  mass  = 0.02 x 23  = 0.51g