Topic 1: Atomic Structure and the Periodic Table Flashcards
(132 cards)
What are all substances made from?
Atoms
What do atoms contain? 3
Nucleus
Protons
Electrons
Where is the nucleus and what does it contain?
It is found in the middle of the atom.
Protons and Neutrons.
What charge does the nucleus have and why?
Positive- because of the protons.
Where is almost the whole mass of the atom concentrated?
The nucleus.
Where specifically do electrons move around the nucleus?
In electron shells.
What charge do electrons have?
Negative
What are tiny and cover a lot of space?
Electrons
What determines the volume of electron orbit?
The size of the atom
What part of the atom has virtually no mass?
The electrons
The number of protons equals what? And why?
The number of electrons (exception of ions).
Because the charge on the electrons is the same size as the charge on the protons, but opposite- so the positive and negative charges cancel out.
Why do ions have an overall charge?
The number of protons doesn’t equal the number of electrons.
What does an ion with charge -2 mean?
It has two more electrons than protons.
What does the atomic number tell you?
How many protons there are.
What does the mass number tell you?
The total number of protons and neutrons in the atom.
How do you get the number of neutrons?
Subtract the atomic number from the mass number
Give the definition of an element
An element is a substance made up of atoms that all have the same number of protons in their nucleus.
What number of what describes what type of atom it is?
The number of protons
How many elements are there on the Periodic Table?
118 (roughly 100)
What are isotopes?
They are different forms of the same element, which have the same number of protons but a different number of neutrons.
Isotopes have the same atomic number but a different…
mass number
Give an example of a pair of isotopes
Carbon-12 (6 PROTONS, 6 electrons, 6 NEUTRONS)
Carbon-13 (6 PROTONS, 6 electrons, 7 NEUTRONS)
Because elements can exist as a number of different isotopes, what is used instead of mass number when referring to the element as a whole?
The relative atomic mass
What is the relative atomic mass?
An average mass taking into account the different masses and abundances (amounts) of all the isotopes that make up the element.