explanation: potassium is an element with atomic number 19, thus it contains 19 electrons. it is a metal which readily loses its electrons to acquire stable configuration of argon which has 18 electrons with completely filled subshells.
c. h20 is reduced
the first equation has h20 part of it, then the second part doesn't have the substance h20
the methane molecule undergoes oxidation and the carbon is oxidized to carbon dioxide and hydrogen to water.
in this reaction there is cleavage of four c-h bonds and two o=o bonds
there will be formation of two c=o bonds and four o-h bonds.
overall due to more bond cleavage energy there will be evolution of energy. thus combustion is an exothermic reaction.