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25 cm^3 of a solution of known 0.2M HCl is neutralised by titration by 21.5cm^3 of NaOH solution. Calculate then concentration of the NaOH solution to 3dp.

Recall n = c *(v/1000) if the volume is in Cm³.

Now, n(HCl)= 0.2 x (25.0/1000)

n(HCl) = 5x10^-3

Since the relationship stoichiometrically is 1:1 (H

Answered by Will F. • Chemistry tutor

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Derive the quadratic formula (Hint: complete the square)

Firstly, the quadratic formula finds the roots of a quadratic equation.
So this means f(x) = 0. A general polynomial with highest power 2 looks like: ax²+ bx +c.
Usings the two fa...

Answered by Riu K. • Maths tutor

3774 Views

Describe the Le Chantelier principle

If a factor affecting the position of an equlibirum is altered, the position fo equlibrium shifts to oppose the effect of the change.

Answered by Sudip S. • Chemistry tutor

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Describe the process of nuclear fission is induced

Single and slow moving neutron strikes a uranium nucleus. This results in the nucleus to be large and unstable. The unstable nucleus splits into two unequal nuclei and some fast neutrons. The neutrons can...

Answered by Sudip S. • Physics tutor

2503 Views

Factorise 7x^2+4x-3

look for common factors but there are not any in this case, it is a quadratic with 3 terms therefore it can be factorised into 2 brackets. First we look at the first term, since 7 is a prime number you ca...

Answered by Reena P. • Maths tutor

4360 Views