Which statement below is true only for homogeneous catalysts?

a. a homogeneous catalyst is a solid substance to which liquid or gaseous reactants will adhere to the surface of the catalyst.

b. a homogeneous catalyst is when the catalyst is in the same physical state as the reactant.

c. a homogeneous catalyst will eventually be consumed in a chemical reaction.

d. no right choice.

Astudent is given a sample of a blue copper sulfate hydrate. he weighs the sample in a dry covered porcelain crucible and got a mass of 23.875 g for the crucible, lid, and sample. the mass of the empty crucible and lid was found earlier to be 22.652 g. he then heats the crucible to expel the water of hydration, keeping the crucible at red heat for 10 minutes with the lid slightly ajar. on colling, he finds the mass of crucible, lid, and contents to be 23.403 g. the sample was changed in the process to very light clue anhydrous cuso4. if there are again 100.0 g of hydrate, how many grams of cuso4 are in it? how many moles of cuso4? (hint: molar mass of cuso4 = 159.6 g / mole. what per cent of the hydrate is cuso4? you may convert the mass of cuso4 to moles.)

If you try to move a piano and are unable to move it, did you perform any work in the scientific sense of the word? yes? or no? this question is worth 20 points! let it be correct!

Which of the following has expanded our knowledge of the universe beyond our solar system the most? a. manned space travel b. the hubble space telescope c. the pioneer and voyager missions d. the international space station