Learners investigate how the type of substance affects electrical conductivity of the
substance. They conduct three experiments using three different substances under the
same conditions, as shown in the table below.
8.1 Define the term electrolyte. (2)
8.2 For the investigation, write down the:
8.2.1 Investigative question (2)
8.2.2 Dependent variable (1)
8.2.3 Independent variable (1)
8.2.4 Controlled variable (1)
8.3 For the investigation, predict with reasons the substance that will yield the
following:
8.3.1 The highest conductivity (2)
8.3.2 Zero conductivity (2)
8.4 The substance tested in Experiment 3 was analysed. It was found to contain
40% carbon, 6,67% hydrogen and 53,33% oxygen.
Determine the molecular formula if the molar mass is 180 g∙mol-1. (7)
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