Which statement must be true about a chemical system at equilibrium?
(1) the forward and reverse reactions stop.
(2) the concentration of reactants and products are equal.
(3) the rate of the forward reaction is equal to the rate of the reverse reaction.
(4) the number of moles of reactants is equal to the number of moles of product.

answer; /// i do believe that the correct answer is (c)nuclear bond

because natural gas is colorless, odorless, and tasteless, distributors add mercaptan (a chemical that smells like sulfur) to give natural gas a distinct unpleasant odor (it smells like rotten eggs). they locate the types of rock that are likely to contain natural gas deposits.