1 Atomic structure Flashcards
What is an atom?
The smallest piece of an element that can still be recognised as an element.
What is a molecule?
Two or more atoms covalently bonded together. Molecules contain a certain fixed number of atoms.
What are atoms made of?
Protons, neutrons and electrons.
Why are they called sub-atomic particles?
Because they are smaller than an atom.
What does the nucleus of an atom contain?
Protons and neutrons.
Where are the electrons found?
At large distances from the nucleus.
What is the relative mass and relative charge of a proton?
Relative mass: 1
Relative charge: +1
What is the relative mass and relative charge of a neutron?
Relative mass: 1
Relative charge: 0
What is the relative mass and relative charge of an electron?
Relative mass: 1/1836
Relative charge: -1
What is an elements atomic number?
The number of protons in an atom.
(Smaller number at the bottom)
What is elements mass number?
The total number of protons and neutrons in the nucleus of an atom.
(Larger number at the top)
How do you find the number of neutrons that an atom has?
Mass number - Atomic number
What is the number of electrons always equal to?
Protons.
What are isotopes?
They are atoms of the same element which have the same atomic number buy different mass numbers.
(Same number of protons but a different number of neutrons)
What is the relative atomic mass of an atom?
It is the average mass of an atom, taking into account the amount of each isotope present in a naturally occurring sample of an element.
What is the formula to calculate relative atomic mass?
(% of isotope1 x mass of isotope1) x (% of isotope2 x mass of isotope2)
/ 100
Where are the groups found on the periodic table?
The vertical columns are groups.
Where are the periods found on the periodic table?
The horizontal rows are called periods.
How are the elements arranged in the periodic table?
In order of atomic number.
What is the number of electrons that each shell can hold?
2, 8, 8, 2
What do you use to draw the electronic configuration of an atom?
The elements atomic number.
What elements have the same number of electrons in their outer shell?
Elements in the same group.
What does the period number of an element tell us?
The number of occupied shells or the highest occupied shell.
How do the group 1 elements react with water?
- They react vigorously
- To form hydrogen and hydroxides
