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What are the three pieces of evidence that disprove the Kekulé model of Benzene?

The enthalpy change of hydrogenation is less exothermic than suggested by the Kekulé model ( -208kJmol^-1 instead of the expected -357kJmol^-1), meaning Benzene is more thermodynamical...

Answered by • Chemistry tutor

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Simplify 5p + 2q – 3p – 3q

Firstly, look at the number in front of the letter 'p'. This is 5p and -3p. By ignoring the 'p', as they both have it, do 5-3 which is 2 and so that part of the answer will be 2p. Then look at the letter ...

Answered by Radhika A. • Maths tutor

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Matthew gets £100 for his 16th birthday and chooses to invest the money into a bank with a 2% annual interest rate. By which birthday will Matthew have more than £150 in his account?

This a geometric sequence with first term 'a' as 100 and common ratio 'r' of 1.02. 100 x 1.02ⁿ > 150 1.02ⁿ > 150/100 =1.02ⁿ > 1.5 log₁₀(1.02ⁿ

Answered by • Maths tutor

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Please can you help me to understand the concept of price elasticity of demand (PED)?

PED is a measure of the responsiveness of demand following a change in the price of a good or service e.g. if the price of good X rose by 20%, PED would measure the extent to which the demand for good X c...

Answered by Tara P. • Economics tutor

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A car is travelling with a velocity of "0.5t^2+t+2" m/s at t=0 (where t is in seconds), find the acceleration of the car at a) t=0 b)t=2

Acceleration can be described as the 'rate of change of velocity' as it is simply how quickly the car is increasing/decreasing in velocity. Therefore as the velocity is described...

Answered by Dominic E. • Maths tutor

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