3.1.4 Energetics, A Level Chemistry, AQA questions with complete solutions.
11 views 0 purchase
Course
3.1.4 Energetics,
Institution
Amsterdam University College (AUC)
What is enthalpy change? - ANS.Heat energy transferred in a reaction at constant
pressure
What are standard conditions for enthalpy change? - ANS.100kPa and stated
temperature (normally 25 degrees celcius)
What values of deltaH do exothermic reactions have? - ANS.Negative (less than 0)
What ...
3.1.4 Energetics, A Level Chemistry, AQA
questions with complete solutions.
What is enthalpy change? - ANS.Heat energy transferred in a reaction at constant
pressure
What are standard conditions for enthalpy change? - ANS.100kPa and stated
temperature (normally 25 degrees celcius)
What values of deltaH do exothermic reactions have? - ANS.Negative (less than 0)
What values of deltaH do endothermic reactions have? - ANS.Positive (more than 0)
What do exothermic reactions do with energy? - ANS.Give out energy
What do endothermic reactions do with energy? - ANS.Absorb energy
Are oxidation reactions endo or exothermic? - ANS.Exothermic
Is combustion endo or exothermic? - ANS.Exothermic
Are thermal decomposition reactions endo or exothermic? - ANS.Endothermic
Is photosynthesis endo or exothermic? - ANS.Endothermic
What happens to reactant bonds? - ANS.They are broken
, What happens to product bonds? - ANS.They are formed
Which bonds are broken: reactant or product bonds? - ANS.Reactant
Which bonds are formed: reactant or product bonds? - ANS.Product
Is energy taken in or released when you break bonds? - ANS.Taken in
Is bond breaking endo or exothermic? - ANS.Endothermic
What values of deltaH does bond breaking have? - ANS.Positive (more than 0)
How does bond breaking energy change as the bond strength increases? - ANS.It
takes more energy to break
Is energy taken in or released when you make bonds? - ANS.Released
Is bond making endo or exothermic? - ANS.Exothermic
What values of deltaH does bond making have? - ANS.Negative (less than 0)
How does bond making energy change as the bond strength increases? - ANS.They
release more energy when formed
If you need more energy to break bonds than is released when bonds are made, what
values of deltaH do you get? - ANS.Positive (more than 0)
If you need less energy to break bonds than is released when bonds are made, what
values of deltaH do you get? - ANS.Negative (less than 0)
What is bond enthalpy? - ANS.The energy required to break bonds
What is the mean bond enthalpy? - ANS.The average energy needed to break a
certain type of bond, over a range of compounds
Why are mean bond enthalpies not exact? - ANS.They are an average of energies
needed to break the bond over a range of compounds
Why may a mean bond enthalpy in a data book be different from the mean bond
enthalpy in a specific molecule? - ANS.The mean bond enthalpy in the data book is
the average for a bigger range of molecules than just the specific molecule.
Why are mean bond enthalpies always positive? - ANS.Breaking bonds is always
endothermic
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 or Stuvia-credit 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 smartdove. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $7.99. You're not tied to anything after your purchase.
