Atomic Structure Flashcards
Define atomic number.
The number of protons in an atom.
Define atomic mass.
The number of protons and neutrons in an atom.
Define isotope.
Atoms of the same element that have the same number of protons but a different number of neutrons.
Mass is expressed as a.m.u. What does this stand for?
Atomic mass unit.
Why are models used to represent atoms?
To help understand atomic properties and behaviour.
What is the atomic charge of a proton?
+1
What is the atomic charge of a neutron?
0
What is the atomic charge of an electron?
-1
What is the atomic mass of a proton?
1
What is the atomic mass of a neutron?
1
What is the atomic mass of an electron?
1/2000 (0.0005)
Electrons rotate at extreme velocities. What does this create?
A cloud, which is known as an orbital.
What defines the chemical identity of an element?
The number of protons.
If an atom were to gain or lose a proton, what would happen to the atom?
It would transmutate into a different atom.
Why does transmutation not occur?
Protons are held together by a strong nuclear force and a lot of energy would be needed to overcome this force.
In a diagram, what symbol represents atomic number?
A
In a diagram, what symbol represents atomic mass?
Z
How do you calculate the number of neutrons an atom possesses?
Atomic mass (Z) - Atomic number (A)
How do you calculate the number of protons an atom possesses?
Atomic number (A).
How do you calculate the number of electrons an atom possesses?
Atomic number (A).
What are the two other isotopes of Hydrogen?
- Deuterium.
2. Tritium.
What are the three important features of Hydrogen’s isotopes?
- They are the entry-port for neutrons.
- There would not be any other chemical element as Helium and other heavier elements could not form.
- They are the fuel for our Sun; there would be no life on Earth if photosynthesis wasn’t possible.
