C 1.1 Atoms Flashcards
(16 cards)
What is an atom?
The smallest part of an element that can still be identified as that element.
What are the three subatomic particles?
Protons, Neutrons, Electrons
Where are the subatomic particles found in an atom?
Protons and neutrons are in the nucleus. Electrons are in shells (energy levels) around the nucleus.
What is the relative charge of a proton?
+1
What is the relative charge of a neutron?
0
What is the relative charge of an electron?
-1
What is the relative mass of a proton?
1
What is the relative mass of a neutron?
1
What is the relative mass of an electron?
Very small (1/1836)
Why is an atom neutral?
Because it has the same number of protons (positive) and electrons (negative), so the charges cancel out.
What is the atomic number?
The number of protons in the nucleus of an atom.
What is the mass number?
The total number of protons and neutrons in an atom’s nucleus.
How do you calculate the number of neutrons?
Mass number – Atomic number = Number of neutrons
What is a chemical symbol?
A one- or two-letter abbreviation used to represent an element, e.g., H for hydrogen, Na for sodium.
What determines what element an atom is?
The number of protons (atomic number).
What are the maximum numbers of electrons in the first few shells?
1st shell: 2
2nd shell: 8
3rd shell: 8 (for GCSE level)
