The following reaction represents the decomposition for water:
2H2O - 2H + O
How many molecules of hydrogen are produced from the decomposition of 12.2 grams of water into its elements?
This is a regular stoichiometry problem. All of these are done the same way. Print this out and remember it.
1. Write the equation and balance it.
Your equation is not correct AND it isn't balanced. It should be
2H2O ==> 2H2 + O2
2. Convert 12.2 g H2O to moles. moles = grams/molar mass.
3. Using the coefficients in the balanced equation, convert moles H2O to moles of hydrogen.
4. IF you wanted grams, then g = moles x molar mass. I would convert to grams even though the problem doesn't ask for it.
5. The problem asks for molecules of H2. You can use the moles from step 3 and calculate it knowing that 1 mole H2 contains 6.022 x 10^23 molecules OR you can use the grams from step 4 and calculate it knowing that 2 g H2 will contain 6.022 x 10^23 molecules.
To determine the number of molecules of hydrogen produced from the decomposition of water, we need to follow a few steps:
Step 1: Calculate the number of moles of water in 12.2 grams.
To do this, we need to know the molar mass of water (H2O). The molar mass is calculated by adding the atomic masses of each element in the molecule.
The atomic mass of hydrogen (H) is approximately 1 gram/mole.
The atomic mass of oxygen (O) is approximately 16 grams/mole.
Molar mass of water (H2O) = 2 x (atomic mass of hydrogen) + atomic mass of oxygen
= 2 x 1 g/mol + 16 g/mol
= 2 g/mol + 16 g/mol
= 18 g/mol
Now, we can calculate the number of moles by dividing the given mass by the molar mass.
Number of moles of water = mass of water / molar mass of water
= 12.2 g / 18 g/mol
= 0.6778 mol
Step 2: Determine the stoichiometry of the reaction.
From the given equation, we can see that 2 moles of water (H2O) decompose to produce 2 moles of hydrogen (H).
Step 3: Calculate the number of moles of hydrogen produced.
Since the stoichiometry of the reaction is 2 moles of water to 2 moles of hydrogen, the number of moles of hydrogen produced will be the same as the number of moles of water in this case.
Number of moles of hydrogen = 0.6778 mol
Step 4: Convert the number of moles of hydrogen to molecules.
To do this, we use Avogadro's number, which is approximately 6.022 x 10^23 molecules per mole.
Number of molecules of hydrogen = Number of moles of hydrogen x Avogadro's number
= 0.6778 mol x (6.022 x 10^23 molecules/mol)
= 4.08 x 10^23 molecules
Therefore, the decomposition of 12.2 grams of water into its elements will produce approximately 4.08 x 10^23 molecules of hydrogen.