Atom Structure Flashcards
Where is the nucleus of an atom?
In the middle
What is in the nucleus of an atom?
Protons and neutrons
where are electrons in atoms?
Surrounding the nucleus in shells
What is the relative mass of a proton?
1
What is the relative mass of a neutron?
1
What is the relative of an electron?
~1/1840
What is the charge of a proton?
+1, positive
What is the charge of a neutron?
0, neutral
What is the charge of an electron?
-1, negative
Describe the plum pudding model of the atom
a large, positive charge with negative electrons arranged randomly as ‘plums’
What are the differences between Dalton’s model of the atom and the current model?
Dalton’s model did not contain protons, neutrons and electrons. Dalton’s model did not have a nucleus. Dalton’s model did not have any charges.
What is the overall charge of an atom?
0
Why is the overall charge of an atom 0?
The numbers of protons and electrons are equal.
Where is most of the mass of an atom?
The nucleus
What is an isotope?
Different atoms of the same element which have the same number of protons but different numbers of neutrons.
What does an atom’s atomic number show you about the atom?
the number of protons
What does an atom’s mass number show you about the atom?
The number of protons + the number of neutrons
How do you work out the number of protons in an atom?
Look at the atomic number
How do you work out the number of electrons in an atom?
Look at the atomic number
How do you work out the number of neutrons in an atom?
Mass number - atomic number
how many electrons can fit in the first shell of an atom?
2
How many electrons can fit in the second shell of an atom?
8
How many electrons can fit in the third shell of an atom?
8
How many protons neutrons and electrons are in sodium? (atomic number = 11, mass number =23)
protons: 11,
electrons: 11,
neutrons: 23-11 =12
what is the electron configuration of sodium? (atomic number = 11)
2,8,1
