Atoms, Compounds And Mixtures (1) Flashcards
All substances are made up of _________
Atoms
Where is the nucleus located in the atom
In the center
The nucleus contains _________ and _________
Protons and neutrons
Almost the whole _________ of the atom is concentrated in the nucleus
Mass
Size-wise the nucleus is ________ compared to the rest of the atom
Tiny
Electrons move around the nucleus in energy levels called __________
Shells
Electrons are ___________ charged
Negatively
Electrons are ______ but cover a lot of space
Tiny
The size of an electron’s __________ determines the size of the atom
Orbit
Electrons have virtually no ___________
Mass
Relative mass and charge of a proton
1
Positive
Relative mass and charge of a neutron
1
Neutral
Relative mass and charge of electrons
1/2000
Negative
The relative mass of a proton is 1
The relative mass of a neutron is 1
The relative mass of an _____________ is 1/2000
Electron
How is the number of electrons similar to the number of protons
It is equal
The _________ on the electrons is the same size as the charge on the protons but _____________
Charge
Opposite
The number of electrons always equals the number of __________ in a neutral atom
Protons
What does the mass number tell you
Total number of protons and neutrons
What does the atomic number tell you
The number of protons
Atoms of the same element always have the same number of _____________ - so atoms of different elements will have different numbers of _____________
Protons
Protons
To get to the number of neutrons, just do:
_________ number - ____________ number
Mass number - atomic number
Which number is the mass number
The top one
Which number is the atomic number
The bottom one
Atoms can join together to form ____________
Molecules
Some molecules are made from just one _____________ (E.g H2 or N2) while other are made up of more than one _____________ (e.g H2O or Co2)
Element
Element
Molecules are held together by ____________ bonds
Covalent
Elements consist of one type of _________ only
Atom
Atoms in gases often go around in __________
Pairs
A molecule with two atoms in it is called a ____________ molecule
Diatomic
What is a compound
A substance that is made of two or more different elements which are chemically joined (bonded) together
The properties of a compound are often totally different from the properties of the original ____________. For example, if a mixture of iron and sulphur is heated, they form the compound iron sulphide. However it is not much like iron (not magnetic) nor sulphur (not yellow)
Elements
There’s no chemical bond between the different parts of a __________. This is opposite to a ____________. The parts can be separated out by physical methods such as ____________
Mixture
Compound
Distillation
A mixture of iron powder and sulphur powder will show the properties of _________ iron and sulphur. (It will be magnetic and yellow)
Both
