A solution is made by adding 12.7 g of calcium sulfate to 502 g of water. What is the percent mass of calcium sulfate in this solution.

It will appear as o2(g) as a reactant 

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Ahigh energy (high speed) particle (alpha or beta or neutron) are shot at the target;

In reversible reaction chemistry equilibrium is attained when the forward and reverse reactions are taking place at the same rate, thus, the concentrations of reactants and products remain the same. a reversible reaction is a chemical reaction where the reactants form products that, in turn, react together to give the reactants back. in irreversible reactions on the other hand, the reactants react to form the products, which cannot revert back into reactants.