Please help explain!!1 The combustion of methane, CH4, releases 890.4 kJ/mol. That is, when one mole of methane is burned, 890.4 kJ are given off to the surroundings. This means that the products have 890.4 kJ less than the reactants. Thus, ΔH for the reaction = - 890.4 kJ. A negative symbol for ΔH indicates an exothermic reaction. CH4 (g) + 2 O2 (g) → CO2 (g) + 2 H2O (l); ΔH = - 890.4 kJ a) How much energy is given off when 2.00 mol of CH4 are burned? b) How much energy is released when 22.4g of CH4 are burned?

in chemistry, adhesion and cohesion are attractive forces that exist between molecules. they hold the molecules together from each other. they are different in that adhesive force exists between molecules of different substance while cohesive force happens between molecules of same substance.

adhesion between water and glass causes water molecules at the edge of water and glass interface to climb up the wall in a narrow glass tube. this is called capillary action. cohesion is what gives glass its shape and causes water to form a droplet.