If g of gold are plated onto a piece of jewelry, how many gold (Au) atoms are present? HOW DO WE GET THERE? How many moles are present in 2.71 g of gold?

Mary is conducting an experiment on how pollution affects plant growth. how can she ensure that her data are reliable?

What mass of natural gas (ch4) must you burn to emit 276 kj of heat?

Hydrogenation reactions, in which h2 and an "unsaturated" organic compound combine, are used in the food, fuel, and polymer industries. in the simplest case, ethene (c2h4) and h2 form ethane (c2h6). if 140 kj is given off per mole of c2h4 reacting, how much heat (in mj) is released when 12 kg of c2h6 forms?