You are given an unknown substance to identify. After making careful observations, you determine that the substance is brittle, dull in appearance, and does not conduct heat. Based on your observations, which of the following most likely describes the unknown substance? Group of answer choices

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 a gas has an initial pressure of 101kpa and a volume of 10l, then it expands to a volume of 20l, what is the new pressure?

What happens to the temperature of a substance when the average kinetic energy of its particles increases?