The arms of humans and the flippers of dolphins have a similar bone structure. so, they’re organs. the legs of a kangaroo and the legs of a jumping spider allow both organisms to jump. however, spiders are invertebrates, and kangaroos are vertebrates. this difference makes their legs structures.

The combustion of methane, ch4, releases 890.4kj/mol. that is, when one mole of methane is burned,890.4 kj are given off to the surroundings. this meansthat the products have 890.4 kj less than the reactants.thus, ah for the reaction = - 890.4 kj. a negative symbolforah indicates an exothermic reaction.ch (g) + 20 (g)> co2 (g) + 2 h0 (1); ah = - 890.4 kga) how much energy is given off when 2.00 mol of ch,are burned? b) how much energy is released when 22.4g of ch. areburned?