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Why can samples of an element have same atomic number but different atomic masses?

This is because the atomic mass of an element is the sum of protons and neutrons. While the proton number is specific for an element, the neutron number can vary for different isotopes of the element. The...

Answered by Francis B. • Chemistry tutor

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State the bonding present in diamonds

Covalent bonding

Answered by Shanali T. • Chemistry tutor

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Write 240 grams as a fraction of 4kg in its simplest form

Firstly, we want to make both measurements in grams. This means that we need to change 4kg (kilograms) to grams. Kilo means 1000, therefore there must be 1000 grams ( kilo gram) in 1kg. If we have 4kg, th...

Answered by Jordan K. • Maths tutor

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The reversible reaction 2 SO2 (g) + O2 (g) <-> 2 SO3 (g) has a delta H value of -197 kJ/mol. Use Le Chatelier's principle to explain what conditions would give the highest equilibrium yield and why industry uses different conditions. (5 marks)

Le Chatelier's principle states that if a system is disturbed - something changes - the system will tend to move in the direction that minimises the change. 3 marks from: The forw...

Answered by Conor C. • Chemistry tutor

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Potassium forms an ionic compound with sulfur. Describe what happens when two atoms of potassium react with one atom of sulfur. Give your answer in terms of electron transfer. Give the formulae of the ions formed.

Potassium (K) is in group 1 of the periodic table, therefore it has 1 electron in it's outer shell. Sulfur is in group 6 so it has 6 electrons in it's outer shell. Ionic bonds occur when electrons are tra...

Answered by Aashish A. • Chemistry tutor

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