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Calculate the mass of sodium amide needed to obtain 550 g of sodium azide, assuming there is a 95.0% yield of sodium azide. Give your answer to 3 significant figures.

2NaNH2 + N2O --> NaN3 + NaOH + NH3 Mr(NaN3) = 65 Mr(NaNH2) = 39 n(NaN3) = 550/65 = 8.46 100% NaN3 = 550/65 x 100/95 = 8.91 n(NaNH2) = 2 x 8.91 = 17.8 m(NaNH2) = 17.8 x Mr = 17.8 x 39 = 694.7 = 695 g
KM
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'Desdemona is a a powerless victim in Othello' to what extent do you agree?

INTRODUCTION: In Othello, ,Shakespeare keeps within the time and social constraints surronding women when creating the tragic victim, Desdemona. I agree with the statement as although one may argue that Desd...
YB
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Give the importance of the lock and key model of an enzyme

The lock and key model only allows one type of specific substrate to form a substrate-activesite complex with each specific type of enzyme. This is due to their complementary shapes, as only one shape and he...
PF
Answered by Paula F. • Biology tutor
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When you integrate, why do you need to add a +C on the end?

Integration can be used to undo differentiation. So if you had an equation that was y=5x+2 and differentiated to get dy/dx=5. When you integrate it you would only get y=5x, so the +2 is lost, to make sure yo...
KM
Answered by Katie M. • Maths tutor
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Describe how a healthy kidney produces urine. (5 marks)

In this question you must first look at the wording. This is a describe question and therefore a description is required but not an explanation. It is worth 5 marks so aim to describe 5 or more reasons how a...
HG
Answered by Hannah G. • Biology tutor
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