C1 - Atomic Structure Flashcards
Define atom
The smallest part of an element that can still be recognised as that element
Define element
A substance made of only one type of atom
Define compound
A substance made of two or more different atoms chemically bonded together
Define molecule
A substance made of more than one atom chemically bonded together (can be atoms of the same type!)
State the masses of the subatomic particles
Protons: 1, neutrons: 1, electrons: almost 0
State the relative charges of the subatomic particles
Protons = +1 neutrons = 0 electrons = -1
What is the plum pudding model of the atom?
A ball of positive charge with negative electrons studded into it
What did Rutherford’s alpha scattering experiment prove?
Atoms have a small dense nucleus with a positive charge.
How did Bohr adapt the model of the atom?
He said electrons orbit the nucleus at specific distances
What did Chadwick’s work give evidence of?
That the nucleus also contained neutrons as well as protons
What is the atomic number of an atom?
The number of protons in an atom
How were elements arranged in the early attempts of the periodic table?
By atomic weight
How are elements in the periodic table arranged?
By atomic number
What do you know about elements in the same group?
They have similar properties (reactions) as they have the same number of electrons in the outer shell
What are periods in the periodic table?
The rows in the periodic table
What are groups in the periodic table?
The columns, numbered 1, 2, 3, 4, 5, 6, 7, 0/8
Why did Mendeleev swap the order of some elements?
So they were in the same group as elements they had similar chemical properties with.
What is crystallisation?
When a solution is heated until crystals start to form then left to cool until all the water evaporates
What does distillation do?
Separates mixture of liquids with different boiling points
What is an isotope?
An atom with the same number of protons but a different number of neutrons.
What type of ions do metals form?
Positive ions as they lose electrons to get a full outer shell cation
What type of ions do non-metals form?
Negative ions as they gain electrons to get a full outer shell
What is group 1 called?
Alkali metals
What is group 7 called?
Halogens
What is group 0 called?
The noble gases
State the trend in the melting points of the alkali metals
Gets lower down the group