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When will le chatelier's principle come into effect? at the beginning of a reaction, when there are only reactants when a reaction has reached chemical equilibrium when a catalyst is added to a reaction mixture when a reaction is occurring but not yet at equilibrium

Which is true of a liquid? it has a definite volume but not a definite mass. it has a definite mass but not a definite volume. it has a definite volume but not a definite shape. it has a definite shape but not a definite volume.

What is the percentage of hydrogen in c2h4