Summary
Summary Topic 1 - Lattice Enthalpy
- Institution
- CCEA
These are the complete notes for the CCEA A2 1 specification and have been created through multiple sources. However, they are not endorsed by CCEA.
[Show more]
Seller
Follow
Content preview
ChemistryTopic 1: Lattice Enthalpy
Standard lattice enthalpy ΔHlatt (Endothermic – Positive value): The enthalpy change when 1 mole of
an ionic compound is converted into its gaseous ions under standard conditions
A large value for lattice enthalpy shows that there are strong electrostatic forces of attraction
between the oppositely charged ions in the lattice.
Born-Haber Cycles
Standard enthalpy change of Formation, ΔHf (Exothermic – Negative value): The enthalpy change
when one mole of a compound is formed from its elements under standard conditions.
e.g. K(s) + ½ Cl2(g) KCl(s)
Standard enthalpy change of Atomisation, ΔHat (Endothermic – positive value): The enthalpy change
when one mole of gaseous atoms is formed from the element in its standard state.
e.g. K(s) K(g)
½ Cl2 (g) Cl(g)
Standard bond dissociation enthalpy, ΔHBDE (Endothermic – positive value): The enthalpy change
required to break 1 mol of a covalent bond under standard conditions.
e.g. Cl2 (g) 2Cl (g)
First ionisation energy, ΔHI1 (Endothermic – Positive value): The energy change required to convert
one mole of gaseous atoms into gaseous ions with a single positive charge.
e.g. K(g) K+(g) + e-
Second ionisation energy, ΔH12 (Endothermic – Positive value): The energy change required to
convert one mole of gaseous ions with a single positive charge into gaseous ions with a double
positive charge.
e.g. Ca2+(g) Ca2+(g) + e-
First Electron affinity, ΔHEA1 (Exothermic – Negative value): The enthalpy change when one mole of
gaseous atoms is converted int gaseous ions with a single negative charge.
e.g. Cl(g) + e- Cl- (g)
Second Electron affinity, ΔHEA2 (Endothermic – Positive Value): The enthalpy change when one mole
of gaseous ions with a single negative charge is converted into gaseous ions with a double negative
charge.
e.g. O-(g) + e- O2-(g)
Charges repel and therefore the gaseous ions must take in energy
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 JArchy123. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for £2.99. You're not tied to anything after your purchase.
Can Stuvia be trusted?
4.6 stars on Google & Trustpilot (+1000 reviews)
50155 documents were sold in the last 30 days
Founded in 2010, the go-to place to buy revision notes and other study material for 14 years now