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Everything on the checklist
What is the law of conservation of mass?
No atoms are lost or made during a chemical reaction so mass of products = reactants
What is Mr?
Mr stands for relative molecular mass
What is RFM?
RFM stands for relative formula mass, which is the sum of the relative atomic masses of all atoms in a chemical formula.
What does the RAM tell us?
The mass of a single atom of an element
Balance Cu + O2 —> CuO
2Cu + O2 —> 2CuO
What is the Mr of ethanol? (C2H6O)
46
What reactions appear to involve a change in mass?
Mg + O2 —> 2MgO, mass seems to increase
Why does mass increase for Mg+O2 —> 2MgO?
Because initially the oxygen is not weighed as you cannot measure the mass of a gas in the air; and the magnesium is reacting with oxygen from the air.
What does measurement uncertainty mean?
The margin of doubt that exists for any measurement; written as ± measurement (e.g. 20cm ± 1cm)
How to calculate measurement uncertainty on a measuring cylinder?
Smallest division/ 2
What is the symbol for the unit mole?
mol
What is the value for the Avogadro constant?
6.02 × 10²³
What is a mole?
6.02 × 10²³ of something
How to find number of moles?
Moles = Mass in g / RAM or RFM
What is 1 mole of a substance in grams equal to?
Its RFM
Calculate the number of moles of 66g of calcium
1.65 mol
Note 
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