# Induced Fission

#### ltlmissmegan

Hello
I am having problems even starting this question and was wondering if someone could at least guide me in the right direction! The question is:
What is the mass of 235 Uranium which when undergoing induced fission would produce the same amount of thermal energy as one ton (1000kg) of coal?

1 person

#### studiot

It's good to see someone who want to do the work themselves and only wants guiding.

So have you looked into how much energy 1000kg of coal will release?

Hint Look up heat of combustion and ask again if unsure.

Right so that gives us the amount of energy we want to produce from our Uranium.

A nuclear reaction results in a loss of total mass which is the source of its energy.

Did you know this?

If you google around you will find that U235 produces a loss of 0.2 atomic mass units (AMU) per mole of U235.

Einstein helps us find out how much energy this represents.

Can you calculate this?

(Hint you should end up with about 200MeV)

However in the real world about 175MeV is spent as kinetic energy for the fission products so is unavailable - you should ask your teacher whether you need to allow for this.

So all that remains is to find out how many moles you need to develop the coal energy.

Let us know how you get on.

1 person

#### ltlmissmegan

So have you looked into how much energy 1000kg of coal will release?

Hint Look up heat of combustion and ask again if unsure.
How would one calculate heat of combustion of coal? The formula that I know of is Q = mcΔT, but because temperature is not given I do not know how to find Q.

#### oz93666

That's a good answer from Studiot IMHO...just one point the KE of products must be included .... the products won't travel far and the kinetic energy is converted into usable heat ...

How to find the heat of combustion of coal ???...

put "How much energy from burning 1 kg coal " in google search