(j)
Using your universal indicator colour chart, estimate the pH of EACH of the soil samples and complete the table below.
| Soil Sample | Estimated pH of Sample |
|---|---|
| A | |
| B | |
| C | |
| D |
[4 marks]
Free CXC Integrated Science Paper 3 May/June 2007 past paper from 2007. Includes a worked answer key. Open the PDF, take a timed test, and study with AI on Caribbean AI.
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CSEC Integrated Science Paper 3 May/June 2007 - Free CXC Past Paper with Answers
Free CXC Integrated Science Paper 3 May/June 2007 past paper from 2007. Includes a worked answer key. Open the PDF, take a timed test, and study with AI on Caribbean AI.
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Every question from this paper as text. See the answers and worked solutions. Questions are the property of the Caribbean Examinations Council; Caribbean AI is not affiliated with CXC.
You are provided with the following:
Proceed as indicated below.
[29 marks]
Half-fill EACH of the four boiling tubes with one of the soil samples: A, B, C and D. Place EACH tube in the test tube rack.
[1 mark]
Add distilled water to EACH boiling tube until it is almost full and observe the appearance of the contents in the tube.
[1 mark]
Record your observations in the space provided below.
A: B: C: D:
[2 marks]
Cover EACH boiling tube with a rubber bung and shake for a few minutes.
[1 mark]
Allow the tubes to settle for 5 minutes and observe the appearance of the contents in the tubes. Record your observations in the space provided below.
A: B: C: D:
[4 marks]
In the space provided below, draw a diagram of one of the boiling tubes to show the appearance of the soil.
[4 marks]
Using a dropper, transfer a small quantity of EACH soil suspension to separate test tubes.
[1 mark]
Use the universal indicator paper to check the pH of EACH of the soil samples, A, B, C and D.
[1 mark]
Insert an appropriate table below and record your results in it.
[3 marks]
Using your universal indicator colour chart, estimate the pH of EACH of the soil samples and complete the table below.
| Soil Sample | Estimated pH of Sample |
|---|---|
| A | |
| B | |
| C | |
| D |
[4 marks]
Plan and design an experiment to confirm that of the four soil samples, A, B, C and D, the most suitable one for growing carrots is Sample C.
[7 marks]
You are provided with the following materials and pieces of apparatus:
Proceed as indicated below.
Using your measuring cylinder, place of solution into the styrofoam cup.
[1 mark]
Leave the sodium hydroxide solution for minutes and then record the temperature.
[1 mark]
Measure of and add to the styrofoam cup. Stir the mixture and record the temperature in degrees Celsius or Centigrade ().
[2 marks]
Repeat (c) above ten times.
[1 mark]
Insert an appropriate table below and record your observations in it.
[8 marks]
On the axes provided below, draw a graph of volume of acid added against temperature in degrees Celsius ().
[6 marks]
Write a word equation for the reaction which is occurring.
[2 marks]
What type of reaction is this?
[1 mark]
For what volume of acid is the maximum quantity of heat energy evolved?
[2 marks]
Why was a styrofoam cup used in performing this experiment?
[1 mark]