Fission and fusion

Question 1

What is nuclear fission

A type of … reaction that is used to … energy from l… and … atoms by … them into … atoms

Answer 1

A type of nuclear reaction that is used to release energy from large and unstable atoms by splitting them into smaller atoms

Question 2

Why is spontaneous fission rare

Answer 2

Because normally the nucleus has to absorb a neutron before it will split

Question 3

What happens when an atom splits

-It forms … new … elements that are … the same ..
-… or 3 … are also …
—>these can be … by another … causing a … of nuclear …

Answer 3

-It forms 2 new lighter elements that are roughly the same size
-2 or 3 neutrons are also released
—>these can be absorbed by another nucleus causing a chain of nuclear fission

Question 4

What happens to the energy in nuclear fission that is not transferred to the kinetic energy stores

Answer 4

It is carried away by gamma rays

Question 5

How is the amount of energy produced by fission controlled

-By … how … the chain … can occur
-using … rods, which are … and lowered inside a … reactor to absorb … and … down the … reaction

Answer 5

-By changing how quickly the chain reaction can occur
-using control rods, which are raised and lowered inside a nuclear reactor to absorb neutrons and slow down the chain reaction

Question 6

What do uncontrolled chain reactions lead to

Answer 6

Lots of energy being released as an explosion

Question 7

What is nuclear fusion

Answer 7

Where 2 light nuclei collide at high speeds and fuse to create a larger, heavier nucleus

Question 8

Why is the mass of the nucleus produce by fusion lighter than the 2 separate nuclei

Answer 8

Some of the mass is converted into energy and is released

Question 9

Which requires more energy fission or fusion

Answer 9

Fusion