Criado por Mel Hughes
mais de 8 anos atrás
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Why do we count only protons and neutrons to calculate the mass number of an atom?
How many protons, electrons and neutrons are there in an atom of 19/9F?
19=mass number
9=atomic number
What are isotopes?
What is the mass of one mole of sodium atoms?
Why is the relative atomic mass of chlorine not a whole number?
Calculate the relative formula mass (Mr) of sodium sulphate, Na2SO4'
(Relative atomic masses: Na = 23, S = 32, O=16)
What is the mass of one mole of magnesium carbonate, MgCO3?
(Relative atomic masses: Mg = 24, C = 12, O = 16)
What is the percentage of carbon in methane, CH4? (A, of C =12, Ar of H =1)
What is the empirical formula of the compound that contains 70% iron and 30% oxygen? (Ar of Fe = 56, Ar of 0 = 16)
Calculate the mass of calcium oxide that can be made from 10g of calcium carbonate in the reaction:
CaCO3 -> CaO + CO2 (Ar of Ca =40, Ar of O =16, Ar of C =12)
A student made 4.4g of calcium oxide from 4.0g of calcium. Calculate the percentage yield
Why is it not usually possible to get 100% yield from a chemical reaction?
Why should chemical manufacturers use reactions with high yields?
What is a reversible reaction?
What method can be used to analyse the colours in food?
What is the main purpose of the gas chromatography column in GC -MS analysis?
How is the relative molecular mass shown in a mass spectrum?
There are two main types of chlorine atom, 35/17Cl and 37/17Cl
(Mass number + Atomic Number)
What name is used for these two types of atom?
There are two main types of chlorine atom, 35/17Cl and 37/17Cl
(Mass number + Atomic Number)
How is an atom of 35/17Cl different from an atom of 37/17Cl
Hydrogen and iodine react to make hydrogen iodine. The equation for the reaction is:
H2 + I2 =2Hl
What type of reaction is this?
What substances in foods can be detected by paper chromatography?
What is the relative formula mass of magnesium fluoride, MgF2?
What is the mass of one mole of aluminium oxide, Al2O3?
What is the percentage by mass of copper in copper (II) carbonate, CuCo3?
A student made some magnesium oxide by burning magnesium in air. The student obtained a yield of 55%. Suggest two reasons why the yield was less than 100%
What is the empirical formula of vanadium oxide that contains 56% of vanadium?
Calculate the mass of zinc chloride that you can make from 6.5g of zinc
Zn +2HCl --> ZnCl2 +H2
Calculate the percentage yield if 9.0g MgSO4 was made from 4.0g MgO
What information can be obtained from the molecular ion peak in a mass spectrum?