A 2.839-g sample of C2H4O was burned in a bomb calorimeter whose total heat capacity is 16.77 kJ/°C. The temperature of the calorimeter increases from 22.62°C to 26.87°C. What is the heat of combustion per mole of C2H4O?
To calculate the heat of combustion per mole of C2H4O, we first need to find the amount of heat released during the combustion.
1. Calculate the change in temperature:
ΔT = final temperature - initial temperature
ΔT = 26.87°C - 22.62°C
ΔT = 4.25°C
2. Convert the mass of C2H4O to moles:
Molar mass of C2H4O = (2 * Atomic mass of C) + (4 * Atomic mass of H) + (1 * Atomic mass of O)
= (2 * 12.01 g/mol) + (4 * 1.01 g/mol) + (1 * 16.00 g/mol)
= 28.05 g/mol
Moles of C2H4O = mass / molar mass
= 2.839 g / 28.05 g/mol
= 0.1012 mol
3. Calculate the total heat released:
Total heat released = heat capacity * change in temperature
= 16.77 kJ/°C * 4.25°C
= 71.34 kJ
4. Calculate the heat of combustion per mole of C2H4O:
Heat of combustion per mole of C2H4O = total heat released / moles of C2H4O
= 71.34 kJ / 0.1012 mol
= 705.5 kJ/mol
Therefore, the heat of combustion per mole of C2H4O is 705.5 kJ/mol.
To calculate the heat of combustion per mole of C2H4O, we need to use the data provided and apply the principles of calorimetry.
Here's how to approach the problem:
1. Calculate the heat absorbed by the calorimeter:
The heat absorbed by the calorimeter can be determined using the formula: q = mcΔT, where q is the heat absorbed, m is the mass, c is the specific heat capacity, and ΔT is the change in temperature.
Given:
Mass (m) = 2.839 g
Specific heat capacity (c) = 16.77 kJ/°C
Change in temperature (ΔT) = 26.87°C - 22.62°C = 4.25°C
Plugging in these values, we get:
q = (2.839 g) * (16.77 kJ/°C) * (4.25°C)
Convert grams to moles:
The molar mass of C2H4O = (2 * Molar mass of C) + (4 * Molar mass of H) + (1 * Molar mass of O)
= (2 * 12.01 g/mol) + (4 * 1.01 g/mol) + (1 * 16.00 g/mol)
= 44.05 g/mol
Moles = (2.839 g) / (44.05 g/mol)
2. Calculate the heat of combustion per mole of C2H4O:
The heat of combustion per mole (ΔH) can be calculated by dividing the heat absorbed (q) by the number of moles of C2H4O burned.
ΔH = q / Moles
Plugging in the values, we get:
ΔH = (q) / (Moles)
Now, you can proceed with the calculations using the provided values.
q = 16,770 x delta T =? J
delta H/g = ?J/2.839
delta H/mol = delta H/g x molar mass