15995256
Description
Flashcards by Oliver Faragher, updated more than 1 year ago
|
|
Created by Oliver Faragher
over 5 years ago
|
|
| Question | Answer |
| What does the conservation of mass state? | "no atoms are lost or made during a chemical reaction" |
| What happens to reactants in a chemical reaction? | They are rearranged into products |
| What is avagdros constant? | 6.02 x 10 to the power of 23 |
| What is all atomic mass relative to? | Carbon 12 |
| Why may some reactions seem to lose mass? | Some of the reactant is lost as a gas |
| Why may some reactions seem to gain mass? | They react with chemicals in the air |
| What is a limiting reactant? | The reactant that is in the lowest amount |
| What is a decimetre cubed? | 1000 centimetres cubed |
| What can a measurement in moles apply to? | Atoms, ions, formulae, equations, electrons, molecules |
| How do you determine the mass of a molecule from its RFM? | The relative formula mass is equivalent to the weight in grams of 1 mol of a substance |
| What is the Avogadro constant? (definition and number) | The number of atoms, molecules or ions in a mole of a given substance 6.02 x10^23 |
| What is molar mass measured in? | g/mol |
| What's the standard unit of concentration? (by mass and by amount) | g/dm cubed mol/dm cubed |
| How can a product be lost? | Filtration Evaporation Transferring liquids |
| What is atom economy? | The measure of the amount of starting materials that end up as useful products 100% atom economy means all reactants are made into products |
| What is another term for atom economy? | Atom utilisation |
| What factors other than atom economy do you need to consider for reactions? | Yield Rate of reaction Equilibrium position (in a reversible reaction) Usefulness of Bi-products |
| Describe the procedure for titration? | 1) Wear safety glass 2) Fill a burette with a recorded volume 3) Pipette 25cm (cu) into a conical flask 4) Place a indicator into the flask (phenolphthalein) 5) Add acid slowly and swirl 6) When the indicator suddenly changes stop the burette and take a reading 7) Repeat steps 2-6 and go slowly when you get near the trial result 8) Repeat until concordant (+/-0.1) |
| How are gases measured with formula mass and volume at room temperature? | Formula mass is measured in grams Its always done at room temperature and pressure The gas would will always occupy 24dm (cu) |
| Relate moles of a gas to its volume | Equal moles of gases occupy the same volume under the same conditions of temperature and pressure |
| What are the 5 defining features of a mole? | Contains molar mass in grams Has Avogadro constant particles In 1dm(cu) its the same If a gas it occupies the same as all other gases of the same mol Reacts with other substances in whole number ratios |
Want to create your own Flashcards for free with GoConqr? Learn more.