If 250L of hydrogen gas are used to reduce copper (||) oxide, what mass of copper is to be expected

your answer is a. the enthalpy of formation for a pure element in its standard state is always positive.

i belive it is water

the population of unionid mussels in the hudson river decreased after zebra mussels were introduced. zebra mussels, a nonnative species, competed with the unionid mussels for food. the zebra mussels were able to outcompete the unionid mussels, allowing the zebra mussel population to increase dramatically over six years. the unionid mussel population decreased due to a lack of food.

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