C1.3 Separating mixtures

What happens in a chemical reaction?

Atoms rearrange to form new substances.

What is the balanced equation for the reaction of sodium and chlorine?

2 Na + Cl2 → 2 NaCl.

What are all substances made up of?

Atoms.

What do we call the columns in the periodic table?

Groups.

What do greenhouse gases cause?

Global warming / climate change.

What is one advantage of recycling metals?

Reduces energy use, saves finite resources, and reduces landfill use.

What is a mixture?

A mixture contains two or more substances that are physically combined but not chemically joined.

How can insoluble solids be separated from liquids?

By filtration.

How can soluble solids be separated from liquids?

By evaporation.

What is the technique called that separates liquids with different boiling points?

Distillation.

How does crystallisation work in the context of a salt solution?

It separates the salt from the solution by evaporating the water.

What is the purpose of the condenser in distillation?

To cool and condense the vapor back into liquid.

Describe the separation process of a mixture of sand, salt, water, ethanol, and iron.

Use a magnet to remove iron, filter to separate sand, distill to separate ethanol and water, then evaporate to obtain salt.

How is a mixture different from a compound?

In a mixture, the proportions are not fixed, and the components retain their properties.

What is an element?

A pure substance that cannot be broken down into simpler substances.

What is a compound?

A substance formed when two or more elements chemically bond together.

What are atoms made up of?

Protons, neutrons, and electrons.

What role do catalysts play in chemical reactions?

They speed up reactions without being consumed.

What is the law of conservation of mass?

Mass is neither created nor destroyed in a chemical reaction.

What is the pH scale used for?

To measure the acidity or alkalinity of a solution.

What is an ionic bond?

A chemical bond formed by the transfer of electrons from one atom to another.

What is a covalent bond?

A chemical bond formed by the sharing of electrons between atoms.

What are the states of matter?

Solid, liquid, gas, and plasma.

What is solubility?

The ability of a substance to dissolve in a solvent.