Chemistry Flashcards
Define an Atom
The smallest unit of matter that makes a chemical element
Define a molecule
Two or more atoms that are bonded together
List the three subatomic particles
Protons - positive
Neutrons - neutral
Electrons - negative
Name the 3 main states of matter
Solid, liquid, gas
How is shape determined
How close the particles are together
i.e. solid can be compressed, liquid can be slightly compressed, gas can be highly compressed.
Why is ice changing to water a physical change
Because the matter remains the same
Give an example of a physical change
Cutting wood
Define a chemical change
When matter is changed so that one or more new substances are formed
Why is digestion a chemical change
Because food is broken down by digestion and a new substance is formed
Give an example of a chemical change
Food digestion, candle wick burning, lighting a match, burning wood
List 2 elements and their functions
Sulphur - building & repairing DNA
Carbon - building blocks to form proteins, carbs & lipids
List 2 compounds and their functions
Water - Lubricate joints, expel waste through urination
Carbon dioxide - regulation of blood pH, respiration
List 2 mixtures and their functions
Tears - Wash away debris, protect eyes from infection
Sweat - temperature regulation, help grip
List 2 electrolytes and their functions
Potassium - Heart muscle and nerve impulses/receptors . Maintain fluid inside our cells
Sodium - Heart muscle and nerve impulses/receptors - Maintain fluids outside our cells
Define an Ionic Bond
Where an element loses or gains an electron