Ch. 2.1 : Atoms, Ions and Compounds Flashcards Preview

Chemistry Module 2 > Ch. 2.1 : Atoms, Ions and Compounds > Flashcards

Flashcards in Ch. 2.1 : Atoms, Ions and Compounds Deck (12):

Define the term 'isotope'

Different atomic forms of the same element with the same number of protons but a different number of neutrons.


Define the terms anion and cation

Anion - a negative ion, which goes to the positive anode
Cation - a positive ion, which goes to the negative cathode


What is the mass number and atomic number?

Atomic number - smaller number - number of protons ( and subsequently electrons )
Mass number - larger number - number of protons and neutrons


Describe the relative sizes of all the parts of an atom.

The nucleus is tiny compared to the rest of the atom, and so there is a lot of empty space in between the atom and electron shells.
The protons and neutrons are roughly the same size, whereas the electrons are smaller.
An electron is about 1/2000th the mass of a proton. ( 1/1836)


Describe the different charges in an atom.

Proton : positive
Electrons : negative
The charge of a proton is equal but opposite to the charge on an electron. The charges balance.
Neutron : neutral / no charge


How do you work out how many electrons there are?

Same as the number of protons.


How can the atomic number be described as the identity of an element?

Every atom of the same element has the same number of protons.

Different elements have atoms that have different numbers of protons.


What letters are used to represent mass number and atomic number?

Mass number : A -> number of protons and neutrons
Atomic number : Z -> number of protons


Why do isotopes react the same way?

Different isotopes of the same element have the same number of electrons. The number of neutrons has no effect on the reactions of an element. Therefore, different isotopes of an element therefore react in the same way.


What differences can exist between isotopes?

Physical properties e.g. Higher mass isotopes will have a higher melting point, boiling point, and density - but the chemical reactions are the same.


What is an ion?

A charged atom. The number of electrons is different from the number of protons.


What are cations and anions?

Cation : positive ion. It has fewer electrons than protons.
Anion : negative ion. It has more electrons than protons.