When hydrogen peroxide (H2O2) is used in rocket fuels, it produces water, oxygen, and heat.
2H2O2(l)⟶2H2O(l)+O2(g)ΔH=−196kJ
How many kilojoules are released when 2.65 moles of H2O2 reacts?
How many kilojoules are released when 234 g of O2 is produced?
Well, well, well, let me do some calculations and make this fun for you!
First, let's calculate the kilojoules released when 2.65 moles of H2O2 reacts. Since the balanced equation tells us that 2 moles of H2O2 produce -196 kJ, we can use the molar ratio to figure it out:
2 moles H2O2 -> -196 kJ
2.65 moles H2O2 -> X kilojoules
Using proportionality, we can set up a handy equation:
(2.65 moles H2O2) / (2 moles H2O2) = X kilojoules / -196 kJ
Solving for X, we can go bananas with the math:
X = (2.65 moles H2O2 / 2 moles H2O2) * -196 kJ
X ≈ -257 kJ
Voilà! Approximately 257 kilojoules are released when 2.65 moles of H2O2 react.
Now, let's move on to the next puzzle. How many kilojoules are released when 234 g of O2 is produced? We need to use a conversion factor to step up our game!
First, we'll convert grams of O2 to moles of O2. The molar mass of O2 is approximately 32 g/mol:
234 g O2 * (1 mol O2 / 32 g O2) ≈ 7.31 moles O2
Now, using the same logic as before, we can determine the kilojoules released:
2 moles O2 -> -196 kJ
7.31 moles O2 -> X kilojoules
Let's put this beast together:
(7.31 moles O2 / 2 moles O2) = X kilojoules / -196 kJ
Using our math wizardry, we find:
X = (7.31 moles O2 / 2 moles O2) * -196 kJ
X ≈ -713 kJ
Boom! It seems like approximately 713 kilojoules are released when 234 g of O2 is produced.
Remember, these calculations are not clowning around! (Well, maybe just a little.)
To calculate the number of kilojoules released when a certain number of moles of H2O2 reacts, you can use the given molar enthalpy change (ΔH).
1. Convert moles of H2O2 to kilojoules released:
Given moles of H2O2 = 2.65 mol
ΔH = -196 kJ/mol
Since the stoichiometric coefficient of H2O2 in the balanced equation is 2, the molar enthalpy change should be multiplied by 2.
Total kilojoules released = (2.65 mol) * (2 mol H2O2/1 mol ΔH) * (-196 kJ/mol) = -1036.6 kJ
Therefore, 2.65 moles of H2O2 will release approximately -1036.6 kJ of energy.
To calculate the number of kilojoules released when a certain mass of O2 is produced, you need to convert the given mass of O2 to moles first:
2. Convert grams of O2 to moles:
Given mass of O2 = 234 g
Molar mass of O2 = 32 g/mol
Number of moles of O2 = (234 g) / (32 g/mol) ≈ 7.31 mol
Since the stoichiometric coefficient of O2 in the balanced equation is 1, the molar enthalpy change remains the same (-196 kJ/mol).
Total kilojoules released = (7.31 mol) * (-196 kJ/mol) = -1432.76 kJ
Therefore, 234 grams of O2 will release approximately -1432.76 kJ of energy.
To find the number of kilojoules released when a certain amount of H2O2 reacts or when a certain amount of O2 is produced, we need to use the given reaction enthalpy (ΔH) and the stoichiometry of the balanced equation.
1. Finding the kilojoules released when 2.65 moles of H2O2 reacts:
- We know that the reaction releases -196 kJ per 2 moles of H2O2, as stated in the given balanced equation.
- First, we need to find the mole ratio between the reaction and the given amount of H2O2. From the balanced equation, the stoichiometric ratio is 2 moles of H2O2 reacting to produce 196 kJ of energy.
- To calculate the kilojoules released when 2.65 moles of H2O2 reacts, we can set up the following proportion:
(2.65 moles H2O2 / 2 moles H2O2) = (x kJ released / -196 kJ)
- Solving for x, we can calculate the kilojoules released:
x = (2.65 moles H2O2 / 2 moles H2O2) * -196 kJ
= -256.6 kJ
Therefore, when 2.65 moles of H2O2 reacts, approximately 256.6 kJ of energy is released.
2. Finding the kilojoules released when 234 g of O2 is produced:
- We know that the reaction releases -196 kJ per 2 moles of H2O2, as stated in the given balanced equation.
- We also need to convert the given mass of O2 (234 g) into moles. The molar mass of O2 is 32 g/mol.
- Moles of O2 = Mass of O2 / Molar mass of O2
= 234 g / 32 g/mol
= 7.3125 moles O2 (rounded to 4 decimal places)
- Now, we can set up the proportion using the mole ratio and the given reaction enthalpy:
(7.3125 moles O2 / 2 moles H2O2) = (x kJ released / -196 kJ)
- Solving for x, we can calculate the kilojoules released:
x = (7.3125 moles O2 / 2 moles H2O2) * -196 kJ
= -710.6 kJ
Therefore, when 234 g of O2 is produced from the given reaction, approximately 710.6 kJ of energy is released.
a.
196 kJ x 2.65/2.00 = ? kJ produced.
b.
2 mols H2O2 = 2*34 = 68 g.
196 x (234/68) = ? kJ produced.