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Live demo · CSEC Biology

1 mark · Difficulty 2/3

During photosynthesis, the gas that is taken in by the plant is:

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CXC CSEC · Chemistry · Sample revision guide

pH Scale and Indicators

Definition. The pH scale measures how acidic or alkaline a solution is, on a logarithmic range from 0 (most acidic) to 14 (most alkaline), with 7 being neutral. Each whole-number step represents a tenfold change in hydrogen-ion concentration — so pH 3 is 100× more acidic than pH 5…

Continues with worked examples on universal indicator, common acids/bases by pH, neutralisation reactions, and exam-style command-word breakdowns for "describe" and "explain" responses.

2,567 words · 234 guides published · Free to read

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