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Chemistry

GCSE

What is the % yield if 12g of magnesium is dissolved in hydrochloric acid to produce 20g of magnesium chloride?

First we need to write the balanced equation for the reaction. In this case it is Mg + 2HCl -> MgCl₂ + H₂. Now we need to work out the maximum theoretical yield of MgCl₂

Answered by Holly W. • Chemistry tutor

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With reference to valencies, describe and explain the differences in reaction as you go down group 1 of the periodic table for the reaction: metal + water -> Metal hydroxide + hydrogen.

As you descend the group, the reactions become more vigorous, more exothermic and have a higher rate of reaction. Lithium will just gently fizz and produce a gas, sodium will melt into a ball shape and fi...

Answered by George N. • Chemistry tutor

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Explain why an atom has no overall charge

As the number of negatively charged electrons is equal to the number of positively charged protons, therefore the overall charge is zero

Answered by Ethan B. • Chemistry tutor

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Explain why increasing the temperature of a reaction increases the rate of the reaction (2)

By raising the temperature of the reaction mixture, the particles have more (kinetic) energy and so move around at a greater rate. This means there are more frequent collisions, due to the increased speed...

Answered by Sam H. • Chemistry tutor

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What is the difference between ionic and covalent bonding?

Covalent bonding is the sharing of a pair of electrons between atoms to make molecules e.g. CO₂, whereas Ionic bonding is the transfer of electrons from one atom to the other to m...

Answered by Natalie S. • Chemistry tutor

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