lesson 9 atomic mass and mass number Flashcards
1
Q
the smaller number in an element is called what (bottom number)
A
atomic number
2
Q
what does the atomic number tell us
A
the number of protons and electrons in atoms of the element
3
Q
the larger number is called what (top number)
A
mass number
4
Q
what does the mass number tell us
A
the total number of proton and neutrons added together
5
Q
how do we work out the number of neutrons
A
mass number - atomic number
6
Q
what’s an isotope
A
atoms of the same element with a different number of neutrons
7
Q
the protons in every element is what
A
fixed (the same)
8
Q
what are ions
A
atoms with an overall charge, this is because ions have lost or gained electrons
9
Q
positive ions have what
A
lost electrons
10
Q
negative ions have what
A
gained electrons
