hree solutions are mixed together to form a single solution. One contains 0.2 mol Pb(C2H3O2)2, the second contains 0.1 mol Na2S, and the third contains 0.1 mol CaCl2. A) Write the net ionic equations for the precipitation reaction or reactions that occur. B) What are the spectator ions in the solution

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.)

Which part of earth’s surface receives the most direct rays from the sun? a) equator b) ocean c) poles d) mountains

Nonpoint source pollution is difficult to control because it