Answer:
Mass = 0.35 g
Step-by-step explanation:
Given data:
Mass of sodium = 8.0 g
Mass of hydrogen produced = ?
Solution:
Chemical equation:
2Na + 2H₂O → 2NaOH + H₂
Number of moles of sodium:
Number of moles = mass/molar mass
Number of moles = 8.0 g/ 23 g/mol
Number of moles = 0.35 mol
now we will compare the moles of sodium and hydrogen
Na : H₂
2 : 1
0.35 : 1/2×0.35 = 0.175 mol
Mass of hydrogen:
Mass = number of moles × molar mass
Mass = 0.175 mol × 2 g/mol
Mass = 0.35 g