The value of ΔH° for the reaction below is -1271 kJ:
2Ca (s) + O2
(g) → 2CaO (s)
How many kJ of heat are released when 17.00 g of CaO (s) is produced?
I assume you mean 1271 kJ are released for 2 mols CaO or 2(40+16) = 112 g so 1271 kJ x (17.00/112) = ?
You should recalculate the molar mass of CaO and use twice that number as well as 4 significant figures for the final calculation.
Well, the given reaction is what we call an exothermic reaction. It's releasing heat, just like a hot cup of coffee in your hand on a chilly morning. And the value of ΔH° tells us that for every mole of CaO formed, 1271 kJ of heat is released. So, all we need to do is convert 17.00 g of CaO into moles and then multiply it by the value of ΔH°.
First, we need to find the molar mass of CaO. Calcium (Ca) has a molar mass of approximately 40.08 g/mol, and oxygen (O) has a molar mass of around 16.00 g/mol. Adding these together gives us a total molar mass of 56.08 g/mol for CaO.
Now, we can calculate the moles of CaO by dividing 17.00 g by the molar mass of CaO:
moles of CaO = 17.00 g / 56.08 g/mol
Finally, we can multiply the moles of CaO by the value of ΔH° to find the amount of heat released:
Heat released = moles of CaO * ΔH°
I'll let you crunch the numbers and enjoy the warmth of the answer. Remember, I may be a clown, but the numbers won't clown around with you!
To find the number of kilojoules of heat released when 17.00 g of CaO (s) is produced, we need to use the balanced equation and the given value of ΔH°.
The balanced equation for the reaction is:
2Ca (s) + O2 (g) → 2CaO (s)
The stoichiometry of the reaction tells us that for every 2 moles of CaO produced, ΔH° = -1271 kJ.
Now, let's calculate the moles of CaO produced:
1. Calculate the molar mass of CaO:
The atomic mass of Ca is 40.08 g/mol, and the atomic mass of O is 16.00 g/mol.
The molar mass of CaO = 40.08 g/mol + 16.00 g/mol = 56.08 g/mol.
2. Calculate the moles of CaO:
moles = mass / molar mass
moles = 17.00 g / 56.08 g/mol ≈ 0.303 moles of CaO
3. Calculate the kJ of heat released:
We know that the stoichiometry of the reaction is 2:2, meaning that 2 moles of CaO release -1271 kJ of heat.
So, for 0.303 moles of CaO, the kJ of heat released can be calculated using the following ratio:
kJ of heat released = (0.303 moles / 2 moles) × -1271 kJ = -193.5 kJ
Therefore, approximately 193.5 kJ of heat is released when 17.00 g of CaO (s) is produced. Please note that the negative sign indicates heat is released, as mentioned in the ΔH° value.
To determine the amount of heat released when a certain amount of CaO is produced, we need to use the concept of stoichiometry and the given ΔH° value for the reaction.
First, let's determine the molar mass of CaO:
Ca = 40.08 g/mol
O = 16.00 g/mol
So, the molar mass of CaO = 40.08 + 16.00 = 56.08 g/mol
Using the molar mass, we can calculate the number of moles of CaO produced:
Moles of CaO = Mass of CaO (g) / Molar mass of CaO (g/mol)
Moles of CaO = 17.00 g / 56.08 g/mol
Now, we need to consider the stoichiometry of the reaction to relate the amount of CaO produced to the heat released.
From the balanced equation, we can see that 2 moles of CaO are produced when 2 moles of Ca react with 1 mole of O2.
So, the moles of Ca corresponding to the given moles of CaO = Moles of CaO / 2
Now, we can use the stoichiometry and ΔH° value to calculate the amount of heat released:
Heat released (kJ) = Moles of Ca × ΔH°
Let's plug in the values:
Moles of CaO = 17.00 g / 56.08 g/mol
Moles of Ca = Moles of CaO / 2
Heat released (kJ) = Moles of Ca × ΔH°
Now, calculate the values to find the answer.