Now we're going to calculate the amount of work done in this reaction.

When a gas is involved, work can be calculated by this equation.

Work is equal minus p times delta v,

where p is the external pressure of 1.5 atmostpheres.

Delta V is a change of volume of final minus initial.

Now, I have got a conversion factor between the work unit or

the energy unit of liter atmospheres to joules.

I know how to go between those two.

So I'm not going to put millilitres into this equation.

I'm going to put it in terms of liters.

So final that's product.

I have 100 millimeters of gas.

That would be 0.1 liters.

And I'm, initially started with 200 millilitres, or 0.2 litres.

Now, when you multiply this out,

you're going to get 0.15 liter atmospheres.

So that is a work unit that is an energy unit.

And it's going to be, since it's an a, it's 0.1 minus 0.2.

So, this is going to be negative and I changed the signs.

So, we have positive work.