CH3OH CO + 2H2 H = +90.7kJ
9. For the forward reaction, is heat being absorbed or released?
10. How much heat would be transferred if 45.0 g of CH3OH is decomposed?
11. What quantity of CH3OH decomposition would lead to an enthalpy change of 18.5 kJ
See your post below.
9. For the forward reaction, heat is being absorbed.
10. To calculate the heat transferred, we can use the equation:
q = (m * ΔH) / M
where:
q is the heat transferred
m is the mass of CH3OH
ΔH is the enthalpy change
M is the molar mass of CH3OH (32.04 g/mol)
Plugging in the values:
m = 45.0 g
ΔH = +90.7 kJ = +90700 J
M = 32.04 g/mol
q = (45.0 g * 90700 J) / 32.04 g/mol
q = 127388.6 J
Therefore, approximately 127388.6 J of heat would be transferred if 45.0 g of CH3OH is decomposed.
11. To determine the quantity of CH3OH decomposition that would lead to an enthalpy change of 18.5 kJ, we can rearrange the heat transfer equation to solve for mass (m):
q = (m * ΔH) / M
Rearranging:
m = (q * M) / ΔH
Plugging in the values:
q = 18.5 kJ = 18500 J
ΔH = +90.7 kJ = +90700 J
M = 32.04 g/mol
m = (18500 J * 32.04 g/mol) / 90700 J
m = 6.511 g
Therefore, approximately 6.511 g of CH3OH decomposition would lead to an enthalpy change of 18.5 kJ.
To answer these questions, we need to understand the heat of reaction (ΔH) and use the concept of stoichiometry.
1. The equation given is the decomposition of CH3OH into CO and 2H2. The positive ΔH value indicates that the reaction is endothermic, meaning heat is being absorbed during the reaction.
2. To calculate the heat transferred during the decomposition of a given amount of CH3OH, we need to use stoichiometry and the molar mass of CH3OH.
- Find the molar mass of CH3OH: 1 carbon (C) atom has a molar mass of 12.01 g/mol, 4 hydrogen (H) atoms have a molar mass of 1.01 g/mol each, and 1 oxygen (O) atom has a molar mass of 16.00 g/mol. Adding them up, we get:
((1 x 12.01) + (4 x 1.01) + 16.00) g/mol = 32.04 g/mol
- Calculate the number of moles of CH3OH in 45.0 g:
45.0 g / 32.04 g/mol = 1.404 mol CH3OH
- Now, use the mole ratio from the balanced equation to determine the heat transferred:
1 mol CH3OH produces +90.7 kJ of heat
So, 1.404 mol CH3OH would produce:
1.404 mol CH3OH x 90.7 kJ / 1 mol CH3OH = 1.27 x 10^2 kJ (to significant figures)
3. To find the quantity of CH3OH decomposition that would lead to an enthalpy change of 18.5 kJ, we can rearrange the previous calculation slightly:
- Calculate the moles of CH3OH that would produce 18.5 kJ of heat:
18.5 kJ / 90.7 kJ/mol = 0.203 mol CH3OH
- Convert moles to grams:
0.203 mol CH3OH x 32.04 g/mol = 6.50 g CH3OH (to significant figures)
Therefore, 6.50 grams of CH3OH decomposition would lead to an enthalpy change of 18.5 kJ.