Does the identity of an atom change if we add or subtract electrons or neutrons? Explain.

If 90.0 grams of ethane reacted with excess chlorine, how many grams of dicarbon hexachloride would form

Each of the following reactions is allowed to come to equilibrium and then the volume is changed as indicated. predict the effect (shift right, shift left, or no effect) of the indicated volume change. drag the appropriate items to their respective bins. co(g) + h2o(g) < => co2(g) + h2(g) (volume is decreased) pcl3(g) + cl2(g) < => pcl5(g) (volume is increased) caco3(s)< => cao(s) + co2(g) (volume is increased)

Why is the melting of ice a physical change ?