The reaction below shows the decomposition of sodium azide into sodium metal and nitrogen gas.
2NaN3(s)-> 2Na(s) + 3N2(s)
An unknown amount of sodium azide (NaN3) reacts and produces 744 mL of nitrogen gas. What mass of sodium metal is produced?

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  =

since the gas volume given is 744mL = 0.744mL

   Therefore input the variables;  

         Number of moles  =   = 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  = 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

in chemistry, adhesion and cohesion are attractive forces that exist between molecules. they hold the molecules together from each other. they are different in that adhesive force exists between molecules of different substance while cohesive force happens between molecules of same substance.

adhesion between water and glass causes water molecules at the edge of water and glass interface to climb up the wall in a narrow glass tube. this is called capillary action. cohesion is what gives glass its shape and causes water to form a droplet.