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Explain what happens to a crystal of iodine when it is heated (5marks)

A crystal of iodine sublimes from its solid state to its gaseous state without turning into a liquid. Iodine forms a molecular covalent crystal. This means that there are strong covalent ...

Answered by Meghna I. • Chemistry tutor

23462 Views

Sodium chloride and sodium metal can both conduct electricity under differing conditions. Give the conditions required for each to conduct electricity and explain how each conducts electricity.

Sodium chloride will conduct electricity only when it is in a liquid state or in solution, this is because the ions are free to move in this state, allowing them to carry charge and conduct electricity. S...

Answered by Tanmayi J. • Chemistry tutor

36358 Views

Find the equation of the tangent to the curve y^3 - 4x^2 - 3xy + 25 = 0 at the point (2,-3).

This is an example of implicit differentiation where we have to consider both the y-terms as well as the x-terms. The first step is to deal with each term on the left hand side individually. This gives us...

Answered by Tanmayi J. • Maths tutor

4674 Views

Differentiate with respect to x: (6x + 7)e^x

Product Rule: dy/dx (uv) = u'v + uv'
Let u = 6x+7 and v = e^x. Using simple disintegartion, u' is 6 and v' is e^x.
Therefore, answer is: 6e^x + (6x +7)e^x

Answered by Aisha R. • Maths tutor

3922 Views

How do you write an effective and concise introduction to a history essay in an exam?

The purpose of an introduction is to show the examiner that you: understand the question being asked, can outline the various ways of approaching said question and that you have a clear argument. To do th...

Answered by Toby P. • History tutor

4554 Views