Determining the mass in grams of each substance

8.42 X 10^18 formula units of barium nitrate

Pls! plant cells and animal cells were observed under a microscope. the characteristics of two cells are listed below. cell p: does not capture sunlight cell q: has cytoplasm but no chloroplast which statement about the two cells is correct? cell q also has a cell wall. cell q also has large vacuole. cell p also has a large vacuole. cell p also has a cell membrane.

In a heat of an engine, if 700 j enters the system, and the piston does 400 j of work what is the final internal (thermal) energy of the system if the initial energy is 1,500 j

Asample of hydrated tin (ii) chloride (sncl2) has a mass of 4.90 g. when it is dehydrated, it has a mass of 4.10 g. which is the correct chemical formula for the hydrate? sncl2•2h2o          sncl2•4h2o          sncl2•6h2o