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Chemistry

GCSE

A compound is found to contain 3.1% Hydrogen, 65.3% Oxygen and 31.6% Phosphorus. Work out its empirical formula.

To answer this question, we need to know the relative number of atoms of each element present. This can be calculated by dividing the amount of an element present in the sample by the relative masses of t...

Answered by Adam B. • Chemistry tutor

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Describe the structure of the periodic table

The elements in the periodic table are arranged in terms of atomic number. i.e. hydrogen is first as it has 1 proton, then helium with 2, lithium with 3 etc.Elements in the same group have the same number...

Answered by Charles W. • Chemistry tutor

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What is the reaction between Zinc and Sulphuric Acid?

When a metal reacts with an acid it forms a salt and hydrogen gas.The salt will be a sulphate due to the acid being H₂SO₄So, Zn + H₂SO

Answered by Charles W. • Chemistry tutor

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What is an equilibrium?

Have you ever tried to run the wrong way down an escalator? then you have experienced a dynamic equilibrium.You are moving up, it is moving down and yet, your actual position isn't changing. In a reaction...

Answered by Jemma S. • Chemistry tutor

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Calculate the percentage composition by mass of Lithium Sulfate, Li2SO4.

(Taken from GCSE WJEC Additional Science Book- First Published in 2012) and I have adapted the answer given.Relative atomic masses: Li = 7 ; S= 32 ; O=161) Calculate molecular mass of lithium sulfate (Li2...

Answered by Elinor L. • Chemistry tutor

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