Top answers

Compare the structures of Diamond and Graphite, making references to the bonding, the shape of the structures, and location of the electrons within the structures. Account for the fact that graphite conducts electricity and diamond does not.

In diamond, each carbon atom forms 4 strong covalent sigma bonds with other carbons, resulting in a tetrahedral 3D arrangement of atoms where all the electrons are fixed in place or localised. In graphite, e...
OW
Answered by Ollie W. • Chemistry tutor
8358 Views

A block of mass (m) is placed on a rough slope inclined at an angle (a) to the horizontal, find an expression in terms of (a) for the smallest coefficient of friction (x), such that the block does not fall down the slope.

The first thing to do as with any mechanics question is draw a force diagram with the weight (mg), the friction (F) and the normal reaction (R). As we are finding the smallest coefficient of friction possibl...
OW
Answered by Ollie W. • Physics tutor
4869 Views

By using the substitution x = tan(u), find the integral of [1 / (x^2+1) dx] between the limits 1 and 0

First we need to change the limits, and by plugging in 1 and 0 to our substitution we find that the limits for u are arctan(1) and arctan(0) (or pi/4 and 0). Then we need to substitute for dx, and by differe...
OW
Answered by Ollie W. • Maths tutor
12662 Views

Which element, Na or Mg is likely to have the higher melting point? Give reasons for your choice

Sodium and Magnesium are both metals, when they are solid they form a metallic lattice held together by the electrostatic force of attractive between the positive metal ions, and the negative delocalised ele...
MP
Answered by Monique P. • Chemistry tutor
22803 Views

Solve the equation (2X + 3) / (X-4) - (2X - 8) / (2X + 1) = 1

In order to solve this equation we need to find a common denominator for the 2 fractions. It is impossible to name the common denominator while working with unknown variables such as x,y etc. but we know fro...
OG
Answered by Octavian G. • Maths tutor
5603 Views