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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
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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
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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 ...
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Answered by Martina M. • Physics tutor
2408 Views

In year 11, 3/7 of pupils go on holiday abroad in the summer break. Out of these, 1/3 go to France. Determine the ratio of pupils who go to France in summer to pupils who do not go to France in summer.

We can approach this question by breaking it into two steps; first use the information given to work out what proportion of pupils in year 11 went to France. Once we have this, we can go on to find the ratio...
AS
Answered by Anisah S. • Maths tutor
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A scalene triangle has 3 angles ABC in degrees, where A = (3x + 7), B = (4x + 5), C = (x + 8). Find the value of largest angle.

Equate all the angles to 180 degrees.3x+7+4x+5+x+8=1808x+20=1808x=160Therefore, x=20 .Hence, A =3(20)+7= 67B =4(20)+5= 85C =20+8= 28 Therefore the largest angle is B.
AP
Answered by Alexander P. • Maths tutor
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