This documents includes every past paper question I could find for Energetics, with the answers. How to use these notes: Just cover the answers and think to yourself what it could be and then check. Try learn all the answers off by heart. I hope you find this helpful!
A student determined a value for the enthalpy change when a sample
of propanone was burned. The heat produced was used to warm
some water in a copper calorimeter.
The student found that the temperature of 150 g of water increased by
8.0 °C when 4.50 × 10−3 mol of pure propanone was burned in air.
Use the student’s results to calculate a value, in kJ mol −1, for the
enthalpy change when one mole of propanone is burned.
(The specific heat capacity of water is 4.18 J K−1 g−1)
Define the term standard enthalpy of combustion.
1. The enthalpy change at a constant pressure when 1 mol of a
compound
2. Is burned completely in oxygen
3. With all reactants and products under standard conditions
, 2
Suggest two reasons why the value obtained by the student in part (c)
is different from the value calculated in part (e)
1. Heat loss
, 3
2. The specific heat capacity of the apparatus was not considered
3. incomplete combustion
4. The water may end up in the gaseous state rather than a liquid
5. Reactants and products may not be in standard states.
1. redox
2. Calcium is extracted by electrolysis
3. calcium is expensive to extract
4. Calcium extraction uses electricity
5. Calcium extraction uses large amount of energy
6. Calcium is a reactive metal
, 4
1. HCl is corrosive
2. H2 is flammable
3. The HCl is easily separated as it is a gas so it will escape
1. Increase in volume
2. Smaller increase in T above room temperature
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller alevelstudent2021. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for £3.49. You're not tied to anything after your purchase.
