atomic structure and the periodic table Flashcards
What is the average radius of an atom?
The average radius of an atom is 0.1 nanometres.
What is the average radius of a nucleus?
The average radius of a nucleus is 0.0001 nanometres.
What are the relative masses and charges of sub-atomic particles?
sub-atomic particle - relative mas - relative charge
proton - 1 - +1
neutron - 1 - 0
electron - very small (1/1800) - -1
What is a compound?
A compound is two or more elements chemically bonded together in fixed proportions. They can only be separated by chemical reactions. They usually have different properties to the elements it’s made from.
What is a molecule?
A molecule is any element(s) chemically joined. (eg. O2)
In 2H20, what does the smaller and larger 2’s represent?
The larger number represents the molecule number. The smaller number represents the atom number.
What is a mixture?
A mixture is two or more elements not chemically bonded together. The properties of each substance is unchanged. They can be separated by physical separation techniques.
What is the chemical formula for ammonia?
ammonia - NH3
What is the chemical formula for carbon monoxide?
carbon monoxide - CO
What is the chemical formula for calcium chloride?
calcium chloride - CaCl2
What is the chemical formula for sodium carbonate?
sodium carbonate - Na2CO3
What is the chemical formula for sulfuric acid?
sulfuric acid - H2SO4
What is the chemical formula for methane?
methane - CH4
What is the chemical formula for nitric acid?
nitric acid - HNO3
Before the discovery of the electron, what did people believe the atom was?
Before the discovery of the electron, people believed the atom was a tiny sphere that couldn’t be divided.