Chemistry 5070/42 — October/November 2021
Cambridge O-Level · Alternative to Practical · worked solutions for every part, with the mark scheme
Topics Experimental Contexts · Analysis, Conclusions and Evaluation · Use of Techniques, Apparatus and Materials · Qualitative Analysis · Observations and Measurements · Planning Experiments and Investigations
A student uses the apparatus to separate a mixture of three alkanes.
Name apparatus A and B.
A ______
B ______
Identify two errors in the assembled apparatus shown in the diagram.
- ______
- ______
The errors are corrected.
The mixture of alkanes is heated in the flask to start the separation.
The boiling points of the alkanes are shown.
| alkane | boiling point / |
|---|---|
| octane | 126 |
| nonane | 151 |
| decane | 174 |
State why the flask is not heated directly with the flame of a Bunsen burner.
______
State why the flask is not heated with a beaker of boiling water.
______
Name a piece of apparatus that is suitable to heat the flask.
______
Name the first alkane collected in the conical flask.
Explain your answer.
alkane ______
explanation ______
State the purpose of apparatus B.
______
The rest of this paper
5 more questions- Q2Qualitative Analysis · Observations and Measurements · Experimental Contexts · Analysis, Conclusions and Evaluation · Planning Experiments and Investigations9M
- Q3Qualitative Analysis7M
- Q4Experimental Contexts · Analysis, Conclusions and Evaluation · Use of Techniques, Apparatus and Materials · Observations and Measurements15M
- Q5Analysis, Conclusions and Evaluation · Qualitative Analysis9M
- Q6Use of Techniques, Apparatus and Materials · Experimental Contexts · Analysis, Conclusions and Evaluation11M