Who introduced planatary model ​

Calcium hydride (cah2) reacts with water to form hydrogen gas: cah2(s) + 2h2o(l) → ca(oh)2(aq) + 2h2(g) how many grams of cah2 are needed to generate 45.0 l of h2 gas at a pressure of 0.995 atm and a temperature of 32 °c?

How many moles of al3+ ions are in 1.25 moles of al2o3

What is the area in square meters of 448 g ai foil that has a thickness of 23921 nm? the density is 2.70 g/cm