Exam (elaborations)
OCR A+Level Chemistry- Module 2 Solutions _1
- Course
- Institution
OCR A+Level Chemistry- Module 2 Solutions _1
[Show more]
Seller
Follow
denicetho
Content preview
OCR A+Level Chemistry- Module 2Solutions
What is the oxidation number for combined 02? - ANS--2
Calculate mass number - ANS-(isotope number x abundance)/100
Moles= - ANS-Mass / Mr
Calculating with moles - ANS-1. Balance equation
2. Calculate moles
3. Ratio
4. Calculate the mass, volume, concentration, etc.
Limiting Factor - ANS-The larger amount of moles
Percentage Yield - ANS-actual yield(mol)/theoretical yield(mol) x 100
Atom economy - ANS-(Molecular mass of desired products/ Molecular mass of all
products) x 100
Gas calculations - ANS-mol=vol(dm3)/24
Concentration= - ANS-moles/volume
Ideal gas equation - ANS-PV=nRT
Calculating empirical formula - ANS-Pretend that you have a 100g sample.
That is, change % to grams.
Convert the grams to moles for each element.
Divide each number by the smallest number.
Multiply the result(if needed) to get rid of any fractions.
Calculating water of crystallisation - ANS-mass of hydrated- mass of sulfate= mass of
water
, find moles of sulphate and water
ratio the moles
What is an isotope? - ANS-atoms of the same element with the same number of protons
but different number of neutrons
Atomic Structure - ANS-Electron on outer shell, neutron and proton in center, nuclei.
Relative isotopic mass - ANS-The mass of an atom of an isotope compared with
one-twelfth of the mass of an atom of carbon-12.
Relative atomic mass - ANS-The weighted mean mass of an atom of an element
compared with one-twelfth of the mass of an atom of carbon-12.
Mole - ANS-the SI base unit used to measure the amount of a substance
Avogardos constant - ANS-6.02 x 10^23 particles
Empirical formula - ANS-the simplest whole number ratio of atoms of each element
present in a compound
molecular formula - ANS-The number and type of atoms in each element of a molecule
Anhydrous - ANS-without water
Hydrated - ANS-with water
Water of crystallisation - ANS-Water molecules that form an essential part of the
crystalline structure of a compound
Strong acid - ANS-an acid that ionizes completely in aqueous solution Strong
base - ANS-A base that dissociates completely into ions in solution. Weak acid -
ANS-an acid that is only slightly ionized in aqueous solution Weak base - ANS-A
base that does not dissociate completely into ions in solution. Alkali - ANS-A base
that dissolves in water
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 denicetho. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $9.65. You're not tied to anything after your purchase.
Can Stuvia be trusted?
4.6 stars on Google & Trustpilot (+1000 reviews)
63613 documents were sold in the last 30 days
Founded in 2010, the go-to place to buy study notes for 14 years now