Solid sodium reacts violently with water, producing heat, hydrogen gas, and sodium hydroxide. How many molecules of hydrogen gas are produced when 27.5g of sodium are added to water? Show your work.
The balanced chemical equation for the reaction between sodium and water is:
2 Na + 2 H2O -> 2 NaOH + H2
From this equation, we can see that 2 moles of sodium produce 1 mole of hydrogen gas. We need to determine how many moles of sodium are in 27.5g.
The molar mass of sodium is 22.99 g/mol, so:
27.5 g / 22.99 g/mol = 1.196 mol
Therefore, 1.196 mol of sodium will produce:
1.196 mol x (1 mol H2 / 2 mol Na) = 0.598 mol H2
Finally, we can use Avogadro's number to convert from moles to molecules:
0.598 mol H2 x (6.022 x 10^23 molecules/mol) = 3.6 x 10^23 molecules of H2
So, when 27.5g of sodium react with water, 3.6 x 10^23 molecules of hydrogen gas are produced.