PLEASE HELP I HAVE THIS TEST TOMORROW AM GIVING MORE POINTS THAN I SHOULD! An unlit match contains approximately 1,000 J of chemical energy. When it burns, the match releases thermal energy and light energy. After it has burned, the remaining match contains 250 J of chemical energy. If the thermal energy was measured to be 400 J, how much light energy did the match emit?

match emit 350 J light energy.

Explanation:

By law of conservation of energy,  total energy before and after reaction for an isolated system remains constant.

Total energy for unlit match = 1000 j

When it burns type of energy released

thermal energy = 400 j

light energy --> it value is unknown which we have to find

also remaining match has 250 joule of chemical energy

applying   law of conservation of energy

energy before match was unlit = energy after match was lit

1000 j = thermal energy + light energy + chemical energy of remaining match

1000 J = 400 J  + light energy + 250 J

light energy = 1000 J - 400J - 250J

light energy = 350 J

Thus, match emit 350 J light energy.