Data and Calculations:
1. Volume of water in calorimeter: 100.0 mL
2. Mass of water in calorimeter (water's density 1.00g/mL): 100.0g
3. Initial Temperature of water in calorimeter:19.5 degrees Celsius
4. Final Temperature of water in calorimeter: 3.0 degrees Celsius
5. Final volume of water in calorimeter: 122.5mL
6. Volume of water from melted ice: 22.5mL
7. Mass of water from melted ice (water's density 1.00g/mL)
8. Temperature change of water in calorimeter: -16.5
9. Find the energy change (deltaH) of water in calorimeter (heat capacity for water 4.18J/gC:_____ (i got -6900J but im not so sure)
10. Energy change (delta H) of water from melted ice: ____ ( i got 140J)
11. Energy change of melted ice: _____ **(main one that i need help on)
12. Energy change per mole of melting ice (deltaH fusion): ____
435.76
To find the energy change (deltaH) of water in the calorimeter, you can use the formula:
deltaH = mass x specific heat capacity x temperature change
Given:
- Mass of water in the calorimeter = 100.0g
- Specific heat capacity of water = 4.18J/g°C
- Temperature change of water in the calorimeter = -16.5°C
Using the formula, substitute the values:
deltaH = 100.0g x 4.18J/g°C x (-16.5°C)
deltaH = -6,897 J
So, the energy change (deltaH) of water in the calorimeter is -6,897 J.
To find the energy change (deltaH) of water from the melted ice, you can use the same formula:
deltaH = mass x specific heat capacity x temperature change
Given:
- Volume of water from melted ice = 22.5 mL
- Mass of water from melted ice = volume x density = 22.5g x 1.00g/mL = 22.5g
- Specific heat capacity of water = 4.18J/g°C
- Temperature change of water from melted ice = -16.5°C
Using the formula, substitute the values:
deltaH = 22.5g x 4.18J/g°C x (-16.5°C)
deltaH = -1,573 J
So, the energy change (deltaH) of water from the melted ice is -1,573 J.
To find the energy change of the melted ice, you need to consider the heat released by the ice to cool down from its initial temperature to its freezing point, and then the heat released during the phase change from solid ice to liquid water.
To calculate the energy change of melting ice, you can use the formula:
deltaH = mass x heat of fusion
Given:
- Mass of water from melted ice = 22.5g
- Heat of fusion for water = 334 J/g (the heat required to melt one gram of ice at 0°C)
Using the formula, substitute the values:
deltaH = 22.5g x 334 J/g
deltaH = 7,515 J
So, the energy change of the melted ice is 7,515 J.
Lastly, to find the energy change per mole of melting ice (deltaH fusion), you can use the molar mass of water and convert the mass of the melted ice to moles.
Given:
- Molar mass of water = 18.015 g/mol
Convert the mass of the melted ice to moles:
moles = mass / molar mass
moles = 22.5g / 18.015 g/mol
moles ≈ 1.249 mol (round to three decimal places)
Now, divide the energy change of the melted ice by the number of moles:
deltaH fusion = energy change / moles
deltaH fusion = 7,515 J / 1.249 mol
deltaH fusion ≈ 6,012 J/mol (round to three decimal places)
So, the energy change per mole of melting ice (deltaH fusion) is approximately 6,012 J/mol.