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Describe the principles of how paper chromatography works

Paper chromatography separates a mixture of solutions by their various solubilities. The less soluble components have a higher affinity to the stationary phase (the paper strip) while more soluble compone...

Answered by Rebekah D. • Chemistry tutor

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How does a vaccination work?

To start we need to ask: what causes an infection? The answer is a pathogen, which is a microbe that causes disease. These can be bacteria or viruses. A vaccine contains dead or inactive pathogens that ar...

Answered by Jessica S. • Biology tutor

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An equation for the reaction is: NiO + C = Ni + CO Calculate the percentage atom economy for the reaction to produce nickel. Relative atomic masses (Ar): C = 12 Ni = 59 Relative formula mass (Mr): NiO = 75 Give your answer to 3 significant figures.

Atom economy is a percentage value which tells you how efficient the product is in comparison to the amount of reactant used.Equation to learn: atom economy = Ar of useful product/A...

Answered by Peter Rory H. • Chemistry tutor

3994 Views

In decimal, what is the most negative number that can be represented using a 12-bit two’s complement binary integer?

In an n-bit two's complement representation scheme, the amount of numbers we can represent is 2ⁿ - 1. In 12- bit, it's 1111 1111 1111, or 4095 in decimal. The largest positive ...

Answered by Marek D. • Computing tutor

18523 Views