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Why is benzene more stable than the theoretical model cyclohexa-1,3,5-triene?

In cyclohexa-1,3,5-triene the molecule has 3 single bonds and 3 double bonds where all the electrons are localised. As a result the energy needed to hydrogenate cyclohexa-1,3,5-triene is (3x -120kJ/mol) =...

Answered by Afia P. • Chemistry tutor

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Given that y =2x^3 + 3/(x^2), find a) dy/dx and b) the integral of y

a) It is useful to rewrite the equation using power rules, so we get y = 2x³ + 3x^-2Now we can simply use the differentiation rules where we multiply the coefficient (number before x)...

Answered by Balint S. • Maths tutor

7144 Views

Alex's rocket lands after 4.56s and Billy's lands after 5.21s. What was the initial (maximum) vertical velocity of both of their rockets as they left the launchpad to 3s.f.?

Application of suvat equation v=u+at. Students acknowledge that at the rocket's maximum height it will have a velocity of 0. They also realise that the time to reach thi s point from launch is half ...

Answered by • Physics tutor

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Draw a diagram of the forces acting on the rocket as it flies vertically upwards, the rocket is flying through air not a vacuum (it's not in space yet!)

They should draw a vague rocket shape pointed upwards. It will have one arrow pointing straight down through the rocket marked "gravity", "g", or "g=9.81kg m/s^2" etc. Anothe...

Answered by • Physics tutor

2250 Views

This Question is a multi-parter but all around the same scenario. Similar to an end of paper A-level physics question.

Alex and Billy are launching the air rockets they made by launching them using a bike pump. They each have a rocket, a launchpad, a bikepump connected to it and their teacher Daniel has two stopwatches. T...

Answered by • Physics tutor

1554 Views