8 - Science Chemical Reactions

energy

Breaking bonds requires _____ and forming bonds releases _____.

endothermic reaction

A reaction in which energy is absorbed is called an_____.

exothermic reaction

A reaction in which energy is released is called _______.

exothermic

All combustion reactions are ___________.

bonds

Chemical reactions break chemical ______ and then form new _______.

absorb

Endothermic reactions ____ energy.

bond energy

Energy used to bread bonds and form bonds is called ___________.

supply

Exothermic and endothermic reactions work together to ____ energy.

release

Exothermic reactions _____ energy.

plant, glucose

Fossil Fuels come mostly from ____ material that used photosynthesis to produce ____.

Exothermic releases energy; endothermic absorb energy.

How are exothermic and endothermic reactions different?

heat and light

In which ways might an exothermic reaction release energy?

light

Sometimes energy is released as ______ instead of heat, like glow sticks, fireflies, jelly fish.

bonds, released

The energy stored in these ____ remains over time and is then ____ when fossil fuels are burned.

photosynthesis

The most important endothermic reaction on Earth is _____.

more

There is _____ energy released when are bonds formed than is used to break the bonds

exothermic reactions

________ produce a great deal of heat and raise the temperature of their surroundings.