Atomic Structure Flashcards
Why do all the isotopes of a element react in the same way
Because they all have the same electron configuration.
How do we determine mass number and abundance of isotopes?
We use a mass spectrometer
State and explain the first step of ToF spec after vaporisation
Ionisation there are 2 ways something can be ionised :
Electron gun (electron impact): sample vaporised and electron is knocked off each particle the high energy electrons to form the 1+ ions. (Used for elements and low Mr compounds)
atoms bombarded with high energy electrons from an electron ‘gun’ to form +1 ions
Electrospray:the sample is dissolved in a solvent and pushed through a small nozzle at high pressure. High voltage is applied to it, causing each particle to gain an H+ ion.(used of high Mr compounds (proteins))
State and explain the 2nd step of ToF spec
Acceleration :positive ions are accelerated by an electric field. This electric field gives the same kinetic energy to all particles. The lighter ions experience a greater acceleration.
State and explain the 3rd stage of ToF spec.
Ion drift : the ions enter region with no electric field. They drift at the same speed as they left the electric field. So lighter ions will be drifting at higher speeds
State and explain the 4th step of ToF spec
Detection:
because lighter ions travel through the drift region at different speeds, they reach the sector quicker than the heavier ions. When the positive ions hit the negatively charged detection plate, they gain an electron producing a flow of charge. The greater the abundance, the greater the current produced.
What effects ionisation energy
Shielding- electrons repel each other due to their negative charge. The greater the number of inner shells of electrons, the greater the repulsion of the outer shell of electrons.
Nuclear charge- The greater the nuclear charge, the greater the attractive force on the outer electrons.
Atomic radii- The larger the atomic radius, the further away the outer electrons are held from the nucleus, and the smaller the nuclear attraction.
What is the basic unit of an element?
Atom
True or False: An atom consists of protons, neutrons, and electrons.
True
What is the charge of a proton?
Positive
What is the charge of an electron?
Negative
Fill in the blank: The nucleus of an atom contains ______ and ______.
protons, neutrons
Which particle has a negligible mass compared to protons and neutrons?
Electron
What is the relative mass of a neutron?
1
What is the atomic number of an element?
The number of protons in the nucleus of an atom.
How do you calculate the number of neutrons in an atom?
Subtract the atomic number from the mass number.
What is the mass number of an atom?
The total number of protons and neutrons in the nucleus.
True or False: Isotopes have the same number of protons but different numbers of neutrons.
True
What is the electron configuration of a carbon atom?
1s² 2s² 2p²
Define ion.
An atom or molecule that has a net electrical charge due to the loss or gain of one or more electrons.
What is the difference between cations and anions?
Cations are positively charged ions, while anions are negatively charged ions.
What does the term ‘valence electrons’ refer to?
Electrons in the outermost shell of an atom.
Fill in the blank: The ______ model describes the atom as having a nucleus surrounded by a cloud of electrons.
quantum
What is the significance of the quantum number?
It describes the energy levels of electrons in an atom.
What does the principal quantum number (n) indicate?
The main energy level of an electron.
True or False: Electrons can occupy the same quantum state within an atom.
False
What is the Pauli Exclusion Principle?
No two electrons in an atom can have the same set of four quantum numbers.
What is the shape of an s orbital?
Spherical
What is the shape of a p orbital?
Dumbbell-shaped
How many orbitals are in a d subshell?
5
What is meant by ‘electron affinity’?
The amount of energy released when an electron is added to a neutral atom.
What is the significance of the electromagnetic spectrum in atomic structure?
It explains how electrons transition between energy levels by absorbing or emitting light.
What is the difference between ground state and excited state of an atom?
Ground state is the lowest energy state, while excited state is when an electron has absorbed energy and moved to a higher energy level.
Definition of a orbital
A regional within an electron that can hold up to TWO electrons with opposite spin.
How do electrons fill orbitals
Fill the lowest energy first
Electrons prefer to fill orbitals on their own and only pair up when there is no space available.
