Atomic Structure Flashcards
What is the relative mass and relative charge of a proton?
relative mass: 1
relative charge: 1+
(These are not the actual charges and masses. They are charges and masses compared with each other in a simple ratio)
What is the relative mass and relative charge of a neutron?
Relative mass: 1
Relative charge: 0
(These are not the actual charges and masses. They are charges and masses compared with each other in a simple ratio)
What is the relative mass and relative charge of an electron?
Relative mass: 1/1836
Relative charge: 1-
(These are not the actual charges and masses. They are charges and masses compared with each other in a simple ratio)
Describe the distribution of mass within an atom.
The mass is concentrated at the nucleus of an atom.
What is the nucleus made up of?
The nucleus is made up of particles called nucleons. There are two types of nucleons: protons and neutrons.
Describe the behaviour of beams of protons, neutrons and electrons in an electrical field.
When subatomic particles are passed between two oppositely charged plates the protons will be deflected on a curved path toward the negative plate because, they are positive. Whereas the electrons will be deflected on a curved path towards the positive plate because they are negative. Neutrons will continue on a straight path because they have no charge.
What is the atomic number(z)?
The atomic number is equal to the total number of protons present in the nucleus of an atom. Atoms of the same element have the same atomic number and number of protons.
What is the mass number (A)?
The mass number/nucleon number (A) is equal to the total number of neutrons and protons in an atom.
How do you find the neutrons in an atom given the nuclied notation?
The number of neutrons in an atom= mass number-atomic number. = a - z.
How do you find the neutrons in an atom given the nuclide notation?
The number of neutrons in an atom= mass number-atomic number. = a - z.
What is an ion?
An ion is a charged atom i.e. the number of protons is not equal to the number of electrons.
When is a positive ion formed?
Positive ions are formed by the loss of electrons. The +ive on ions is equal to the number of electrons lost.
When is a negative ion formed?
Negative ions are formed by the gain of electrons. The -ve charge is equal to the number of electrons gained.
What is an isotope?
Isotopes are atoms with the same atomic number and a different mass number. Isotopes are atoms with the same number of protons but a different number of neutrons.
Do isotopes have similar or different chemical properties and why?
Isotopes have similar chemical properties because they have the same number of electrons.
Do isotopes have similar or different physical properties and why?
Isotopes have different physical properties such as small differences in density because they have different masses/ different number of neutrons.
Which sub-atomic particle is responsible for the chemical properties of the atom?
The electrons are responsible for the chemical properties.
What are two ways isotopes can be represented?
isotopes can be represented by nuclide notation. Chemists also name them by emitting the proton number and placing the nucleon number after the name for example the isotopes of hydrogen can be called:
hydrogen-1
hydrogen-2
hydrogen-3
What are the three naturally occurring isotopes of hydrogen?
The three naturally occurring isotopes of hydrogen are:
1. Protium (atomic number 1 and mass number 1)
2. Deuterium (one proton, one neutron, and one electron)
3. Tritium (one proton and two neutrons)
They all have the same number of protons.
Protium or common hydrogen is the only atom without a neutron in its nucleus.
What is the definition of cathode?
The negatively charged electrode in electrolysis is called the cathode. Positively charged ions move towards the cathode.
What is the definition of anode?
The positively charged electrode is called the anode. Negatively charged ions move towards the anode.
What is the definition of a nucleon number?
The nucleon number (A) is the number of protons plus neutrons in the nucleus of an atom. This is also known as the mass number.
What is a principal quantum number (n)?
A principal quantum number (n) represents the shell that the electrons occupy. These principal quantum numbers are numbered according to how far they are from the nucleus. The lowest energy level, n=1, is closest to the nucleus, the energy level n=2 is further out, the third shell is n=3 and the 4th shell is n=4.
What is the relationship between principal quantum numbers and energy?
The larger the principal quantum number, the higher the energy and the further the shell is from the nucleus.