I need help with question 1

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

Phosgene (carbonyl chloride), cocl2, is an extremely toxic gas that is used in manufacturing certain dyes and plastics. phosgene can be produced by reacting carbon monoxide and chlorine gas at high temperatures: co(g) cl2(g)⇌cocl2(g) carbon monoxide and chlorine gas are allowed to react in a sealed vessel at 477 ∘c . at equilibrium, the concentrations were measured and the following results obtained: gas partial pressure (atm) co 0.830 cl2 1.30 cocl2 0.220 what is the equilibrium constant, kp, of this reaction

In chemistry, the type of an atom (what element it is) is determined by: a) the number of protons it contains in its nucleus.b) the number of neutrons it contains in its nucleus.c) the number of protons it has in a cloud around the nucleus.d) the number of neutrons it has in a cloud around the nucleus.e) the number of electrons it exchanges with its neighbors.