1. A sample of carbon contained 98.90% carbon-12 and 1.10% carbon-13. Calculate the relative atomic mass of carbon

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2. Complete the following expression: amount (in moles) =

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3. In a chemical reaction, 250 kJ/mol is taken to break all the bonds and 280 kJ/mol is released when new bonds are formed. What is the overall molar enthalpy of the reaction?

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4. A compound that contained 24.24% Carbon. 4.04% Hydrogen and 71.72% Chlorine and has a relative molecular mass of 99. Calculate the empirical formula and the molecular formula.

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5. State the expression for calculating % yield.

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6. Work out the empirical formula of an oxide of chlorine contains 7.1 g of chlorine and 1.6 g of oxygen.

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7. To determine the formula of a metal oxide by combustion, magnesium is heated in a crucible. Why is the crucible is cooled, weighed, reheated, cooled, re-weighed, and so on?

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8. State the expression for calculating molar concentration

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9. Use Q=mcΔT and c=4.18J/°C/g. A strip of magnesium is added to a beaker with 200cm³ of copper (II) sulfate. The temperature starts at 21.7°C and rises to a maximum of 23.1°C. What is the total heat energy change?

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10. State the units of molar enthalpy change.

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11. A sample of hydrogen chloride gas has a volume of 48 dm³. What amount of hydrogen chloride is this?

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12. Calculate the relative formula mass(Mr) of hydrated copper (II) sulfate (CuSO₄.5H₂O)

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13. What mass of calcium bromide will fully react with 71g of chlorine?

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14. A graph shows the solubility of sodium chloride in water at 50°C is 34g/100g. At that temperature, what mass of sodium chloride will dissolve in 200g water?

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15. What is the meaning of the word mole in Chemistry?

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16. What is meant by the term molecular formula?

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17. Name this piece of lab equipment

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