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Chemistry

GCSE

How do endothermic and exothermic reactions differ?

Endothermic reactions take in heat from the surroundings, whereas exothermic reactions release heat to the surroundings. Exothermic reactions release heat as the energy released from the bonds being made ...

Answered by Miss Louise M. • Chemistry tutor

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Describe the structure of an atom and an ion.

An atom consists of three sub-atomic components; protons, neutrons and electrons. The nucleus contains protons and neutrons. Electrons orbit the nucleus. Protons have a positive charge, electrons have a n...

Answered by Priya J. • Chemistry tutor

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How does the reactivity of Group 1 Metals with water change down the group?

This is due to the shielding effect. When a group 1 metal reacts with water the reaction proceeds through the formation of an ionic species MOH where M is any group 1 metal. Since the species for...

Answered by Joseph G. • Chemistry tutor

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Describe how crude oil is separated into fractions in industry

Crude oil is made of many hydrocarbons that can have differing lengths. A hydrocarbons length determines it's boiling point due as a

Answered by Ben H. • Chemistry tutor

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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

2123 Views