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What is the best way to structure answers to evaluation questions (24 marks)?

For longer answer questions, examiners want to see you demonstrate a higher level of analysis and evaluation. The short mark answers rely solely on knowledge but the longer marks require you to do more wi...

Answered by Kajal P. • Geography tutor

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(a) By using a suitable trigonometrical identity, solve the equation tan(2x-π/6)^2 =11-sec(2x-π/6)giving all values of x in radians to two decimal places in the interval 0<=x <=π .

say (2x-π/6)=qtan²q = sec²q-1so sec²q-1= 11 - sec q sec²q + sec q -12 = 0(sec q -3) (sec q + 4) = 0sec q = 3 or -4because 0<=x<= πso -π/6 <= q <= 11...

Answered by Zhaohui Z. • Maths tutor

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Describe the changes in equilibrium of ethanol production from ethene and water (enthalpy of reaction is ∆H = - 46 kJ/mol) when: (a) a high pressure is applied; (b) ethanol concentration is increased; (c) temperature is increased; (d) a catalyst is used.

The equation for the reaction (would be given for this type of question but I ran out of space): C₂H₄ (g) + H₂O (g) ⇌ C₂H₅OH (g) ∆H = - 46 kJ/molQues...

Answered by Aiste A. • Chemistry tutor

7874 Views

Using principles of structure and bonding, explain why sulfur has a higher melting point than phosphorus

Sulfur, which is naturally S₈has more electrons than Phosphorus, which is naturally P₄. Therefore the Van der Waals between molecules is stronger in Sulfur than it is in Phosphorus,...

Answered by Dalvin S. • Chemistry tutor

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