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85 cm^3 of 0.05 mol/dm^3 sulfuric acid is used to neutralise 15 cm^3 of sodium hydroxide of an unknown concentration. Given that the chemical formula of the reaction is 2NaOH + H2SO4 => NA2SO4 + 2H2O, find the concentration of the sodium hydroxide.

Firstly, calculate the number of moles of sulfuric acid that reacts with the sodium hydroxide, using the equation; n = MV/1000 , where n is the number of moles, M is the concentration (in mol/dm³

Answered by Joshua N. • Chemistry tutor

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Find the equation of a straight line that passes through the points (2,7) and (5,3)

Since we're told the line is straight, the equation of the line will be of the form y = mx + c.The gradient of the line, m, is the change in y divided by the change in x ; m = (3-7)/(5-2) = - 4/3.Therefor...

Answered by Joshua N. • Maths tutor

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write x^2 + 10x - 6 in the form (x+a)^2 + b

(x + 5)² - 5² - 6(x + 5)² - 25 - 6(x + 5)² - 31

Answered by Thomas B. • Maths tutor

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solve; (6x - 2)/2 - (4x+7)/3 = 1-x

numerical answer x =-1/8 oe (or equivalent), but I am more interested in the method usedMy methodsimplify first fraction to 3x-1, multiply both sides by 3, collect like terms, divide through...

Answered by Ruth L. • Maths tutor

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How is DNA replicated?

DNA replication is a multi stage process which is carried out in the nucleus of the cell. We know that DNA is in a double helix structure and for replication to occur it must be unwound into two single st...

Answered by William G. • Biology tutor

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