Quelpr
2 marksAcids, Bases, Mixtures and Household Chemicals

CSEC Integrated Science · May/June 2016 · Paper 2 · Question 3(b)(iii)

Table 2 shows the pH of four brands of toothpaste (A, B, C, D) tested by Frank.

Identify the toothpaste brand with an incorrect pH in Table 2 and give a reason.

This question uses a figure or table from the paper — you'll see it when you practise.

The mark scheme is shown once you've answered.

Practise this question

Other parts of this question

  1. 3(a)Suggest THREE habits, other than brushing regularly, that could explain why Cindy has fewer cavities than her twin Joan.[3 marks]
  2. 3(b)(i)Name a substance that can be used to measure the pH of toothpaste.[1 mark]
  3. 3(b)(ii)Arrange the four toothpaste brands in descending order of acidity (most acidic first) using their letters.[2 marks]
  4. 3(b)(iv)State a possible source of error that may have caused Frank to obtain the incorrect result.[1 mark]
  5. 3(b)(v)State ONE component in toothpaste that helps strengthen teeth.[1 mark]
  6. 3(c)(i)Name ONE acidic and ONE alkaline substance present in the human digestive system.[2 marks]
  7. 3(c)(ii)Name ONE digestive enzyme that operates best in an alkaline medium.[1 mark]
  8. 3(c)(iii)Explain the scientific principle by which antacids relieve digestive problems.[2 marks]

More practice: the rest of this paper · more Acids, Bases, Mixtures and Household Chemicals questions · all CSEC Integrated Science past papers