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State and explain the tests necessary to positively identify an unknown sample as copper carbonate

If portion of the unknown were to be placed in a blue Bunsen flame, a green-blue flame would appear. This indicates the presence of copper. If a portion of the unknown were to be added to dilute hydrochlo...

Answered by Matthew S. • Chemistry tutor

7287 Views

Expand and Simplify: 16=(x-3)(x+3)

16 = (x-3)(x+3) --> 16 = x^2+3x-3x-9 --> 16 = x^2-9 --> x^2=25 --> x = +5 or -5

Answered by Thaarabi T. • Maths tutor

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Explain how crude oil is split into fractions? Give an example of a substance collected at the top of the column. [5 marks]

Crude oil is made up of a mixture of substances.Crude oil is vapourised before it enters the column.The column is hotter at the bottom and cooler at the top (around 350 degrees at the bottom, and 50 degre...

Answered by Thaarabi T. • Chemistry tutor

3271 Views

Give three reasons for why biomass may not be transferred from primary consumers to organisms at higher trophic levels in the food chain. [3 marks]

Some energy is lost via the the primary organism's waste products (such as urine and faeces).Some energy is lost as heat produced as a product of respiration.Energy produced by respiration may be used for...

Answered by Thaarabi T. • Biology tutor

13595 Views

How do I work out the magnification of an image?

For these types of questions, start by writing out the equation for magnification: Magnification = (size of image) / (size of real object). Then, find the values given in the question that can be plugged ...

Answered by Chloe R. • Biology tutor

32033 Views