When conducting tests for the presence of a specific organic substance, it is very useful to include an Experiment control.
<h3>What are chemical changes?</h3>
A chemical change is defined as a change in which a change in chemical composition takes place. A new substance is formed in these reactions. Chemical reactions are usually characterized by a change in colour, heat change, precipitate formation and evolution of bubbles.
Example: Oxidation of magnesium
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A is direct variation because the line does not curve and x and y are in a direct ratio
It consist of integral proteins and trans-membrane proteins and peripheral proteins as well
