Atomic and Electron Structure Flashcards
State all the relative charges of the subatomic particles
Neutron: 0 (neutral)
Electron: 1-
Proton: 1+
State all the relative masses of the subatomic particles
Neutron: 1
Proton: 1
Electron: 1/1836
What is atomic number?
The number of protons in the nucleus of an atom
What is mass number?
The number of protons and neutrons in a nucleus
Define isotopes
Atoms of the same element with the same number of protons but a different number of neutrons
Why do isotopes have similar chemical properties?
They have the same electron configuration (so react similarly)- as neutrons do not affect how an element reacts
What are ions?
Charged substances which contain a different number of electrons than protons
Define relative isotopic mass (3)
The mass of an atom of an isotope compared with one-twelfth of the mass of an atom of carbon-12
Define relative atomic mass (RAM) (3)
The weighted mean mass of an element relative to one-twelfth of the mass of an atom of carbon-12
What is meant by the term ‘weighted mass’
The mean mass when taking all the relative abundances of each isotope of an element into account
Ne-21 atoms make up 0.27% by mass of a sample of Neon gas. Neon has a relative atomic mass of 20.2
Two other isotopes of Neon were present in the sample- ^20Ne and ^22Ne.
Use the information to calculate the % by mass of each of these isotopes. (4)
^Ne20= 89.865%
^Ne22=9.865%
What are shells made up of?
Sub shells and orbitals
Shells are also regarded as what?
Energy levels
How could the relative masses of carbon isotopes be found experimentally?
Mass spectrometry
What is meant by an atomic orbital? (2)
A regional within an atom, around the nucleus, that can hold upto two electrons with opposite spins
What is shell number referred to as?
Principle quantum number
Max number of atomic orbitals and electrons in each sub-shell?
s=2 electrons, 1 orbital
p=6 electrons, 3 orbitals
d=10 electrons, 5 orbitals
f=14 electrons, 7 orbitals
State what orbitals are present in each principle quantum number, upto n=4
1- s
2- s,p
3- s,p,d
4- s,p,d,f
How many electrons can be held in each principle quantum number, up to n=4?
1- 2 electrons
2- 8 electrons
3- 18 electrons
4- 32 electrons
Shape of an s orbital?
Spherical
Shape of a p orbital?
Dumb-bell shaped
Explain the Aufbau principle in terms of electron filling, giving an example (3)
Electrons fill orbitals with the lowest energy first, with opposite spins. The 3d sub-shell fills after the 4s sub-shell because 4s has lower energy.
What block is Sodium in?
s block
What block is bromine in?
p block
What block is zinc in?
d block
What block is americium in?
f block
Why is nitrogen described as a p block element? (1)
Because nitrogen’s highest energy electron is found in a p orbital
Electron configuration of chromium? (Cr) explain why. (2)
1s2 2s2 2p6 3s2 3p6 4s1 3d5
Because like this Cr can be most stable, as it avoids repulsion in the 4s orbital so all 3d electrons can be singly occupied
Electron configuration of copper? (Cu) explain why. (2)
1s2 2s2 2p6 3s2 3p6 4s1 3d10
To obtain a fully occupied 3d sub shell, allowing copper to become stable
What is meant by the term ‘weighted mass’?
The mean mass taking into account the relative abundances of all the isotopes of an atom
