Question

If 38g of sodium hydroxide reacts with 28g of carbon, how many grams of sodium carbonate are produced?

Answer 1

Answer:

Mass of sodium carbonate = 33.92 g

Explanation:

Given data:

Mass of sodium hydroxide = 38 g

Mass of carbon = 28 g

Mass of sodium carbonate produced = ?

Solution:

Chemical equation:

6NaOH + 2C → 2Na + 3H₂ + 2Na₂CO₃

Now will calculate the number of moles of reactants:

Number of moles of sodium hydroxide:

Number of moles = mass / molar mass

Number of moles = 38 g/ 40 g/mol

Number of moles = 0.95 mol

Number of moles of carbon:

Number of moles = mass / molar mass

Number of moles = 28 g/ 16 g/mol

Number of moles = 1.75 mol

Now we will compare the moles of both reactant with sodium carbonate.

                         C           :         Na₂CO₃

                         2           :           2

                       1.75         :         1.75

                  NaOH          :       Na₂CO₃      

                    6               :           2

                     0.95       :           2/6×0.95 = 0.32  

Number of moles of sodium carbonate produced by sodium hydroxide are less so it will limiting reactant.

Mass of sodium carbonate:

Mass = number of moles × molar mass

Mass = 0.32 mol × 106 g/mol

Mass = 33.92 g