Question

Sodium metal and water react to form sodium hydroxide and hydrogen gas:

Answer 1

Answer:

Mass of sodium react = 8.63 g

Explanation:

Given data:

Mass of sodium hydroxide produced = 15 g

Mass of sodium react = ?

Solution:

Chemical equation:

2Na + 2H₂O  → H₂ + 2NaOH

Number of moles of sodium hydroxide:

Number of moles =  mass/ molar mass

Number of moles = 15 g/ 40 g/mol

Number of moles = 0.375 mol

Now we will compare the moles of Sodium and sodium hydroxide.

                        NaOH         :         Na

                          2               :          2

                        0.375         :       0.375

Mass of Sodium:

Mass = number of moles × molar mass

Mass = 0.375 mol× 23 g/mol

Mass = 8.63 g