Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
17 Cards in this Set
- Front
- Back
|
What is relative atomic mass?
|
Ar = Average mass of an atom/ 1/12th the mass of 1 atom of carbon12
|
|
|
What is relative molecular mass?
|
Mr = Average mass of an entity/ 1/12th the mass of 1 atom of carbon12
|
|
|
Convert 1345cm3 to dm3
|
1345/1000 = 1.345dm3
|
|
|
How do you calculate number of moles?
|
moles = Mass/ Mr
|
|
|
What is the equation for concentration?
|
Concentration (mol dm-3) = number of moles/ volume (dm3)
|
|
|
What is the ideal gas equation?
|
P x V = n x R x T Pressure (Pa) x Volume (m3) = number of moles x gas constant (J K-1 mol-1) x temperature (K) |
|
|
How do you convert degrees C to Kelvin?
|
Temperature in degrees + 273
|
|
|
Rearrange the ideal gas equation to find V
|
V = nRT/ P
|
|
|
Rearrange the ideal gas equation to find P
|
P = nRT/ V
|
|
|
Rearrange the ideal gas equation to find the number of moles
|
n = PV/ RT
|
|
|
What steps would you go through to find the empirical formula of a substance?
|
1. Find the masses of each of the elements 2. Calculate the number of moles of each element 3. Convert the number of moles to a whole number ratio by dividing by the smallest number of moles |
|
|
What is the empirical formula?
|
The simplest whole number ratio of atoms of each element in a compound
|
|
|
What is the Molecular formula?
|
The actual number of atoms of each element in a compound
|
|
|
How would you find the molecular formula of a substance using the empirical formula and the relative molecular mass?
|
Relative molecular mass/ relative mass of empirical formula = the number of units of the empirical formula in the molecular formula
|
|
|
How do you calculate % atom economy?
|
(Molecular mass of desired product/ sum of molecular mass of all reactants) x 100
|
|
|
How do you calculate % yield of a reaction?
|
(number of moles of a specified product/ theoretical maximum number of moles of the product) x100
|
|
|
Why would people aim for an atom economy of 100%
|
It is economically beneficial to businesses because it will require less energy and reactants to produce a given amount of product if the atom economy of a reaction is higher. A high atom economy may reduce the production of a harmful waste product such as carbon monoxide. |
