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
mols Na = grams/molar mass
Using the coefficients in the balanced equation, convert mols Na to mols H2.
Now convert mols H2 to molecules H2. There are 6.02E23 molecules in 1 mol H2. And you have ///// mols H2.
ok thanks for the answer but how do you actually do it?
To determine the number of molecules of hydrogen gas formed when 48.7 g of sodium reacts with water, we need to use stoichiometry.
1. Calculate the number of moles of sodium:
molar mass of sodium (Na) = 22.99 g/mol
moles of sodium = mass of sodium / molar mass of sodium
moles of sodium = 48.7 g / 22.99 g/mol
moles of sodium = 2.12 mol (rounded to two decimal places)
2. Determine the stoichiometric ratio between sodium and hydrogen gas:
From the balanced equation, we see that 2 moles of sodium react to produce 1 mole of hydrogen gas.
3. Calculate the moles of hydrogen gas produced:
moles of hydrogen gas = moles of sodium / stoichiometric ratio
moles of hydrogen gas = 2.12 mol / 2
moles of hydrogen gas = 1.06 mol (rounded to two decimal places)
4. Determine the number of molecules of hydrogen gas:
Avogadro's number (NA) = 6.022 x 10^23 molecules/mol
number of molecules of hydrogen gas = moles of hydrogen gas * NA
number of molecules of hydrogen gas = 1.06 mol * (6.022 x 10^23 molecules/mol)
number of molecules of hydrogen gas = 6.38 x 10^23 molecules (rounded to two decimal places)
Therefore, when 48.7 g of sodium are added to water, approximately 6.38 x 10^23 molecules of hydrogen gas are formed.
To calculate the number of hydrogen gas molecules formed when 48.7 g of sodium reacts with water, you need to follow these steps:
Step 1: Determine the number of moles of sodium
To find the number of moles, divide the given mass of sodium (48.7 g) by its molar mass.
The molar mass of sodium (Na) is 22.99 g/mol.
Number of moles of sodium = (Given mass of sodium) / (Molar mass of sodium)
= 48.7 g / 22.99 g/mol
≈ 2.119 mol
Step 2: The balanced chemical equation for the reaction between sodium and water is:
2 Na + 2 H2O -> 2 NaOH + H2
From the equation, we see that for every 2 moles of sodium, we get 1 mole of hydrogen gas (H2).
Step 3: Calculate the number of moles of hydrogen gas
Since we know that 2 moles of sodium produces 1 mole of hydrogen gas,
Number of moles of hydrogen gas = (Number of moles of sodium) / 2
= 2.119 mol / 2
≈ 1.060 mol
Step 4: Convert moles to molecules
To convert moles to molecules, we use Avogadro's number, which states that there are 6.022 x 10^23 molecules in 1 mole.
Number of molecules = (Number of moles) x (Avogadro's number)
= 1.060 mol x 6.022 x 10^23 molecules/mol
≈ 6.381 x 10^23 molecules
Therefore, approximately 6.381 x 10^23 molecules of hydrogen gas are formed when 48.7 g of sodium reacts with water.