To calculate an answer to the correct number of significant figures, you must complete all calculations first and then round your final answer as the very last step. in part c, you are asked to calculate the volume of a rectangular prism that has a length of 5.6 cm, a width of 2.1 cm, and a height of 6.6 cm. you can calculate the volume of a prism by multiplying the area of the base times the height. you already calculated the area of the base as 2.1cm×5.6cm in part a.

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.)

In the cathode ray tube experiment, j. j. thomson passed an electric current through different gases inside a cathode ray tube in the presence of an electric field. in which two ways did this experiment change scientists’ understanding of the atom?

Displacement is the slope of a velocity vs. time graph a. true b. false