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When propanal is reacted with potassium cyanide under weakly acidic conditions the resulting mixture does not rotate plane polarised light. Explain this observation.

A common mistake is to answer this question with the explanation that the light is not rotated because no optical isomers are present. However, this is incorrect. The only other time where plane polarised...

Answered by Sally D. • Chemistry tutor

4249 Views

Explain the stages of an ECG trace.

The P wave is caused by the contraction of the atria, forcing the blood into the ventricles. The sinoatrial node, produces a wave of depolarisation which causes the atria to contact and therefore the p w...

Answered by • Biology tutor

2963 Views

For the function f(x) = 4x^3 -3x^2 - 6x, find a) All points where df/dx = 0 and b) State if these points are maximum or minimum points.

Part a) requires you to find df/dx for the given function. To do this, we differentiate the function once, which is done by multiplying the power of each 'part' with the part itself and subtracting 1 from...

Answered by Martin M. • Maths tutor

3505 Views

What factors influence the rate of photosynthesis?

There are 3 factors that can influence the rate of photosynthesis: light intensity, carbon dioxide concentration and temperature. Light intensity influences photosynthesis as light is required during the ...

Answered by Ruby S. • Biology tutor

9318 Views