You are Here: Home

# AS - Sodium Azide Ideal Gas (+ a bit of moles) watch

1. I've been able to do all other questions, but this one threw me :

A manufacturer plans to produce an airbag of capacity 70 dm^3. Assuming that the temperature of Nitrogen gas in the airbag is 40C, and that the pressure inside the bag when fully inflated is 150000Pa, calculate:

a) the number of moles of nitrogen needed
which i found to be 4.04 mol (3sf)

b) the number of moles of sodium azide required

c) the mass of sodium azide needed.

but im not sure how to work out the last 2, at the top it said "You need to find out what sodium azide is and how it can produce nitrogen"

2HCl + Mg -> MgCl2 + H2

the number of moles for HCl is 0.5, so the number of moles for hydrogen would be 0.25. so to find the mass, would it be 0.25?

Thanks for your help on either/both question(s)!!!

Sana x
2. For the first question 2NaN3 --> 2Na + 3N2 - so two moles of solid sodium azide produces 3 moles of nitrogen gas

for the second question 0.5 moles does indeed produce 0.25 moles of hydrogen gas (H2) so now find the mas
3. (Original post by EierVonSatan)
For the first question 2NaN3 --> 2Na + 3N2 - so two moles of solid sodium azide produces 3 moles of nitrogen gas

for the second question 0.5 moles does indeed produce 0.25 moles of hydrogen gas (H2) so now find the mas

ooooh thats great!! thankyou so much for your help!

could you possibly tell me what sodium azide is? and also for the second question, i meant was the mass 0.25 as the Mr is 1?

Thankyou again!
4. (Original post by just_sanaa)
ooooh thats great!! thankyou so much for your help!

could you possibly tell me what sodium azide is? and also for the second question, i meant was the mass 0.25 as the Mr is 1?

Thankyou again!
sodium azide is (Na)+(N=N=N)-

I knew what you mean't - but remember there are two hydrogens in the gas molecule

### Related university courses

TSR Support Team

We have a brilliant team of more than 60 Support Team members looking after discussions on The Student Room, helping to make it a fun, safe and useful place to hang out.

This forum is supported by:
Updated: November 15, 2008
Today on TSR

### Edexcel C3 Maths Unofficial Markscheme

Find out how you've done here

### 3,398

students online now

Exam discussions

### Find your exam discussion here

Poll

The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.

Register Number: 04666380 (England and Wales), VAT No. 806 8067 22 Registered Office: International House, Queens Road, Brighton, BN1 3XE