Hey there! Sign in to join this conversationNew here? Join for free
x Turn on thread page Beta
    • Thread Starter

    Please could you help me on the following question:
    One method used to inflate air bags in cars is to use nitrogen produced chemically from the decomposition of sodium azide:
    2NaN3(s) = 2Na(s) +3N2(g) (equation 1)
    The sodium formed reacts with potassium nitrate to give more nitrogen:
    10Na + 2KNO3(s) = K2O(s) +5Na2O(s) + N2(g) (equation 2)

    a) In what ratio (by mass) must the sodium azide and potassium nitrate be mixed in order that no metallice sodium remains after th reaction.

    b) Calculate the total mass of the solid mixture needed to inflate a 60dm^3 air bag at room temperature and atmospheric pressure.

    Not sure on the first part of the question, but for the second you can use the ideal gas equation: PV = nRT

    Note: be careful with the 60dm^3, the unit for volume in the ideal gas equation is m^3.
Are you going to a festival?
Help with your A-levels

All the essentials

The adventure begins mug

Student life: what to expect

What it's really like going to uni


Essay expert

Learn to write like a pro with our ultimate essay guide.

Uni match

Uni match

Our tool will help you find the perfect course for you

Study planner

Create a study plan

Get your head around what you need to do and when with the study planner tool.

Study planner

Resources by subject

Everything from mind maps to class notes.

Hands typing

Degrees without fees

Discover more about degree-level apprenticeships.

A student doing homework

Study tips from A* students

Students who got top grades in their A-levels share their secrets

Study help links and info

Can you help? Study help unanswered threadsRules and posting guidelines

Groups associated with this forum:

View associated groups

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

Write a reply...
Reputation gems: You get these gems as you gain rep from other members for making good contributions and giving helpful advice.