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State whether the following conduct electricity as solid or molten: Aluminium, Aluminium fluoride, Boron tribromide

We start with aluminium (Al). Al conducts electricity in both solid and molten states, this is because Al has metallic bonding between fixed positive Al^(3+) ions and delocalised electrons. The delocalise...

Answered by Tom T. • Chemistry tutor

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Find the general solution of: y'' + 4y' + 13y = sin(x)

First we find the auxilary equation by substituting y with m^0, y' with m^1 and y'' with m^2. We get m^2 + 4m + 13 and find the roots using the differential equation, m = (-4 +- (16-4x1x13)^0.5)/(2x1).

Answered by Tom T. • Further Mathematics tutor

9112 Views

Solve 5x^2 - 9x + 4 = 0 using the quadratic formula

The quadratic formula is (-b±sqrt(b^2-4ac))/2a where a is the coefficient of the x^2 term, b is the coefficient of the x term and c is the number. So, in this case a=5, b=-9 and c=4. Substitute this into ...

Answered by Matilda P. • Maths tutor

9520 Views

Solve these equations simultaneously: (1) 5x - 10z = -45 and (2) 9x = -5z + 80

There are two methods to solve this equation. 1) Rearrange equation 2 to get all the xs and zs on the left hand side (9x+5z=80). Multiply either equation to get an equal number of xs or zs in both equatio...

Answered by Matilda P. • Maths tutor

3919 Views

Which compound is a member of the same homologous series as 1-chloropropane? A. 1-chloropropene B. 1-chlorobutane C. 1-bromopropane D. 1,1-dichloropropane

It's B. Chlorobutane

In explaining this answer, I'd test the students knowledge of what a homologous series is. And then we'd draw out the alternative answers and I'd ask the student to explain why...

Answered by Joe P. • Chemistry tutor

14615 Views