1. https://www.youtube.com/watch?v=-bXrsUOpgeg

2. Examiners report Chemistry additional science (Jan 2013 Foundation paper)

4. Question 1 (Low Demand) (a) The relative mass of a proton particle was usually correctly given as 1. A common incorrect answer for the mass of the electron was also 1. Indications of plus or minus were ignored by the examiners. (b) The majority of students realised that the atomic number of the oxygen atom was 8 and that the mass number was 16. Some guesses were evident. (c) and (d) were generally well answered. The identification of the correct symbol in (c)(ii) posed most problems. Question 2 (Low Demand) (a)Guesses were evident here, with just under half of students gaining one mark, and only a quarter of students gaining both marks. (b)Many students scored credit by reference to the high melting point of the silicon dioxide or stating that it would withstand high temperatures. Vague answers involved detail about the bonding or the insulating effect of the silicon dioxide. (c) and (d) Generally well answered.

6. Question 1 (Low Demand) (a) The relative mass of a proton particle was usually correctly given as 1. A common incorrect answer for the mass of the electron was also 1. Indications of plus or minus were ignored by the examiners. (b) The majority of students realised that the atomic number of the oxygen atom was 8 and that the mass number was 16. Some guesses were evident. (c) and (d) were generally well answered. The identification of the correct symbol in (c)(ii) posed most problems. Question 2 (Low Demand) (a)Guesses were evident here, with just under half of students gaining one mark, and only a quarter of students gaining both marks. (b)Many students scored credit by reference to the high melting point of the silicon dioxide or stating that it would withstand high temperatures. Vague answers involved detail about the bonding or the insulating effect of the silicon dioxide. (c) and (d) Generally well answered.

9. Mark scheme