Chemical changes Flashcards
(23 cards)
What is an atom?
The smallest particle of matter, which all things are made of.
What is an element?
A pure substance that is made up of one type of atom.
Example: gold
How many elements are there on the periodic table?
118 elements
Give an example of an element which atoms do not join together.
Helium
Give an example of an element which atoms join together to make molecules.
Oxygen and hydrogen
What gives elements their properties?
The arrangement and behaviour of its atoms
Name 5 properties of metals.
Shiny, hard, strong, high melting and boiling points, often magnetic, conduct electricity
Name 5 properties of non-metals.
Dull, soft, not strong, low melting and boiling points, not magnetic, do not conduct electricity
What does sonorous mean?
Makes a ringing sound when hit (metals)
What does malleable mean?
Easy to reshape without breaking (metals)
What is a compound?
A substance made up of two or more different elements, chemically joined together.
What is a chemical bond?
A strong force holding atoms in a compound together.
Give an example of a compound and its elements?
Water > oxygen and hydrogen elements
What is rearranged during a chemical reaction?
Atoms e.g. iron + sulfur = iron sulfide
What is the equation for conservation of mass?
Mass of reactant + mass of reactant > mass of product
Name the product created by these two reactants: copper and oxygen.
Copper Oxide
Name the product created by these two reactants: sodium and carbon dioxide.
Sodium Carbonate
How many elements in Na₂CO₃
3 - sodium, carbon, oxygen
How many atoms of sodium in Na₂CO₃
2
How many atoms of carbon in Na₂CO₃
1
How many atoms of oxygen in Na₂CO₃
3
What is the scientific name for burning fuels?
Combustion
What 3 things are needed for combustion to happen?
Oxygen, heat, fuel
