solid sodium reacts violently with water, producing heat, hydrogen gas, and sodium hydroxide. how many molecules of hydrogen gas are formed when 48.7 g of sodium are added to water?

2Na + 2H2O ------> 2NaOH + H2

convert grams to moles then use the equatino to do moles of Na to moles of H2O then convert moles of H2O to molecules by using avogadros number (6.022e23) I believe

Samantha has a good plan.

Thx :)

kojb

To determine the number of molecules of hydrogen gas formed when 48.7 g of sodium reacts with water, we need to follow a step-by-step process:

1. Calculate the number of moles of sodium using its atomic mass: The atomic mass of sodium (Na) is approximately 23 g/mol.
Number of moles = Mass / Atomic mass
Number of moles of sodium = 48.7 g / 23 g/mol = 2.12 mol (rounded to two decimal places)

2. Use the balanced chemical equation to find the mole ratio between sodium and hydrogen gas: According to the equation, 2 moles of sodium (2Na) react to produce 1 mole of hydrogen gas (H2).
Therefore, the mole ratio is 2:1 (sodium:hydrogen).

3. Calculate the number of moles of hydrogen gas that can be produced:
Number of moles of hydrogen gas = Number of moles of sodium x (1 mole of H2 / 2 moles of Na)
Number of moles of hydrogen gas = 2.12 mol x (1 mol H2 / 2 mol Na) = 1.06 mol (rounded to two decimal places)

4. To convert moles to molecules, use Avogadro's number: 1 mole = 6.022 x 10^23 molecules.
Number of molecules of hydrogen gas = Number of moles of hydrogen gas x Avogadro's number
Number of molecules of hydrogen gas = 1.06 mol x 6.022 x 10^23 molecules/mol = 6.4 x 10^23 molecules (rounded to two significant figures)

Therefore, when 48.7 g of sodium reacts with water, approximately 6.4 x 10^23 molecules of hydrogen gas are formed.