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What are the factors that affect the rate of a chemical reaction?

For a reaction to occur molecules must collide with energy greater than or equal to the activation energy, in the correct orientation. The factors affecting the rate of a reaction are: Pressure of reacting g...
AJ
Answered by Amelia J. Chemistry tutor
3773 Views

Sketch y = 9x – 4x^3, showing where the curve crosses the x axis.

First you should look at the equation and try and get a sense of the general shape of the graph. The highest power in here is a 3, so this is a cubic graph. The coefficient (number in front of the x^3) is a ...
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Answered by Anais E. Maths tutor
6006 Views

Solve (x^2 - 4)/(2x+4)

The common mistake the students make is to simplify the fraction before factorising numerator and denominator. Here, we need to see that the numerator: x^2 - 4 is a difference between squares , i.e. A^2 - B^...
MM
Answered by Martina M. Maths tutor
4354 Views

A student of mass m=50kg runs an experiment. He throws a ball of mass m = 400g from a height h = 20m. What will be the speed of the ball he records just before it touches the ground?

First, we need to see what the important information in this problem is: the mass of the student is irrelevant as the problem focusses on the ball. So we now know that the important information is: m = 400g ...
MM
Answered by Martina M. Physics tutor
2364 Views

“Mao's ideology was the primary cause for the failure of the Great Leap Forward of 1958 to 1962.” Assess the validity of this view.

Getting started: This question is asking us to assess the validity of a particular view which means that we need to relate the interpretation to the evidence that we have, and assess how valid/accurate this ...
JF
Answered by Jacob F. History tutor
3385 Views