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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

6068 Views

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

2714 Views

What is the difference between an exothermic and endothermic reaction?

Exothermic = A reaction that transfers energy to its souroundings therefore the temperature of the sourounding increases (gets hotter). Can you think of an example? E.g. combustion, neutralisation. As hea...

Answered by Priscilla E. • Chemistry tutor

3621 Views

Explain the electronic configuration of Sodium (Na) and how this relates to its position in the periodic table.

Firstly we must use the periodic table to look at the number of protons (11) contained within a sodium atom. This tells us how many electrons are contained within the shells of that atom as these two are ...

Answered by Luke S. • Chemistry tutor

16309 Views

Which factors should be altered in chemical reaction between zinc (s) and hydrochloric acid (l) in order to speed up the rate of reaction?

Increasing acid concentration- increased number of reactant particles means they are more crowded so there is a greater chance of the particles collidingIncreasing temperature- reactant particles have mor...

Answered by Fatimah R. • Chemistry tutor

2504 Views