2H2O2 --> 2H2O +O2
If a 250mL bottle of hydrogen peroxide solution containing 3% H2O (by mass) completely decomposed how many liters of gas would it generate. Assume that one mole of gas occupies a volume of 22.4 L and that the density of the solution is 1 g/mL.
so basically since you have 250ml of solution, therefore you have 250g of H2O2 (i think you might have put in a typo)...
now you calculate number of moles of H2O2 (the molar mass is approx 34 g/mol) with the formula number of moles = mass/molar mass
now use mole ratios to find out that its 2:1 so the number of moles of O2 is half that of the number of moles of H2O2...
divide the number of moles of peroxide by two and multiply by 22.4L
that should be your answer
3% by mass means there are 3 g H2O2/100 g solution. With a density of 1 g/mL, 100 g solution will occupy 100 mL; therefore, we have 3 g H2O2/100 mL or 3 x (250/100) = 7.5 g H2O2 in the bottle.
Convert 7.5 g H2O2 to moles.
Convert moles H2O2 to moles O2 using the equation.
Volume = 22.4 L/mole x #moles = ??
Post your work if you get stuck.
ahhh crud sorry i forgot about the % of H2O2
go with DrBob
To determine the number of liters of gas produced when the hydrogen peroxide solution decomposes, we need to calculate the moles of hydrogen peroxide and then use the stoichiometric ratio to find the moles of oxygen gas produced. Finally, we will convert moles of oxygen gas to liters using the given volume-to-mole ratio.
Let's break down the problem into steps:
Step 1: Calculate the mass of hydrogen peroxide in the solution.
Given that the density of the solution is 1 g/mL and the volume of the solution is 250 mL, the mass of the solution is 250 mL * 1 g/mL = 250 g.
Since the solution is 3% hydrogen peroxide by mass, we can calculate the mass of hydrogen peroxide:
Mass of H2O2 = 3% * 250 g = 7.5 g.
Step 2: Convert the mass of hydrogen peroxide to moles.
To convert grams to moles, we need to use the molar mass of hydrogen peroxide. The molar mass of H2O2 is calculated as follows:
Molar mass of H2O2 = (2 * atomic mass of H) + (2 * atomic mass of O)
= (2 * 1.008 g/mol) + (2 * 16.00 g/mol)
= 34.016 g/mol.
Now, we can calculate the number of moles:
Moles of H2O2 = Mass of H2O2 / Molar mass of H2O2
= 7.5 g / 34.016 g/mol
≈ 0.220 mol.
Step 3: Use the stoichiometric ratio to find the moles of oxygen gas.
According to the balanced equation, 2 moles of hydrogen peroxide decompose to form 1 mole of oxygen gas. Therefore, we can calculate the moles of oxygen gas produced:
Moles of O2 = 0.220 mol H2O2 × (1 mol O2 / 2 mol H2O2)
= 0.110 mol O2.
Step 4: Convert moles of oxygen gas to liters.
As per the given information, 1 mole of gas occupies a volume of 22.4 L; therefore, we can calculate the volume of oxygen gas produced:
Volume of O2 = Moles of O2 × Volume-to-mole ratio
= 0.110 mol O2 × 22.4 L/mol
= 2.464 L.
Therefore, if the 250 mL bottle of hydrogen peroxide solution containing 3% H2O2 (by mass) completely decomposed, it would generate 2.464 liters of oxygen gas.