8F The periodic table Flashcards
What are the vertical columns in the periodic table known as?
The vertical columns are called “groups”.
What is an element?
An element only has one type of atom.
What is a compound?
A compound is made from more than one type of atom chemically joined together.
What type of element is shown on the left hand side of the bold line?
Metals
Chemical changes are irreversible. What does this mean?
Irreversible changes cannot be changed back. New products have been made eg baking a cake.
Physical changes are reversible. What does this mean?
Reversible changes can be changed back. No new products have been made eg melting ice.
Name three properties of metals.
- Lustrous / Shiny
- Flexible
- Malleable
- High melting point
- High boiling point
How did Medeleev arrange elements in to groups?
Mendeleev arranged elements in to groups that had similar chemical properties.
Which group of the periodic table is known as the halogens?
Group 7 is also known as the halogens.
What is formed when an alkali metal reacts with water?
When an alkali metal reacts with water a metal hydroxide (eg Lithium hydroxide, Sodium hydroxide) and hydrogen are produced.
Describe the reaction of lithium and water.
When lithium is added to water it floats and fizzes around on the surface until it disappears.
Describe the reaction of sodium and water.
When sodium is added to water it fizzes rapidly, melts in to a ball and disappears quickly.
Describe the reaction of potassium and water.
When potassium reacts with water it bursts in to a lilac flame and disappears quickly.
What is a molecule?
A molecule is the name given when 2 or more atoms are stuck together.
It doesn’t matter whether they are the same element or not. You can have a molecule of an element or a molecule which is made of many diferent elements = a compound.
How many elements in KMnO4?
Threre are 3 elements in KMnO4?
Each element has a different symbol starting with a capital letter. So the easy way to work out the answer is to count capital letter!
K = potassium
Mn = manganese
O = oxygen
Explain why in a chemical reaction the mass of the products is the same as the mass of the reactants.
In a chemical reaction the atoms of the reactants are just rearranged during the reaction (no atoms are lost or gained) so the mass of the products is the same as the mass of the reactants.
What is the difference between a molecular structure and a lattice?
A molecule is made of small groups of atoms. A lattice is made of billions of atoms joined together.
