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a) Give a balanced equation for the complete combustion of butane, b) Explain how this would change if there was insufficient oxygen present, and explain the problems this causes

C 4 H 10 + 6.5O 2 -> 4CO 2 + 5H 2 O If there is not enough oxygen, incomplete combustion will occur, so CO (carbon monoxide) will be formed, carbon will form soot, and unburnt hydrocarbons will be release...
AP
Answered by Abigail P. • Chemistry tutor
11853 Views

How do I use verbal aspect in the past tense?

In Russian, verbal aspects are used to indicate the state of the action that you are talking about. In English we can distinguish between ongoing actions (e.g. “I have been reading a book”) and completed act...
EB
Answered by Emma B. • Russian tutor
2062 Views

How many times further away from the pivot point of a seesaw does someone of double the weight have to sit in order for the it to balance?

Sum of moments in equilibrium must equal 0. The sum of clockwise moments must equal the sum of anticlockwise moments. W1 is the force exerted on the seesaw by the heavy person at distance D1 from the pivot a...
RM
Answered by River M. • Physics tutor
3650 Views

How can I factorise 2(x^2)+3x+1=0 ?

This quadratic equation is in the form ax^2+bx+c=0 (a=2, b=3, c=1), where there is a coefficient in front of X 2 term. First we have to multiply a and c. we then have to find two numbers z and y which multip...
JR
Answered by Jonathan R. • Maths tutor
3523 Views

What is Fractional Distillation and how does it work?

Fractional Distillation is a method used in industry to separate different sized hydrocarbons (long chains that consist of hydrogen and carbon ). This is useful as it means crude oil can be separated into mo...
FP
Answered by Fred P. • Chemistry tutor
4382 Views