Topic 1 - Atomic Structure and the Periodic Table Flashcards
What is the radius of an atom?
0.1 nm (1*10^-10m)
What are the main structures of an atom?
Nucleus
Electrons
Where is the nucleus?
In the middle of the atom
What is in the nucleus?
Protons
Neutrons
What is the radius of the nucleus?
1*10^-14m
What is the nucleus’s charge?
Positive (protons)
Where is the mass of the atom concentrated?
In the nucleus
How are electrons present in an atom?
They move around the nucleus in electron shells
What is the charge of an electron?
Negative (-1)
What is the charge of a proton?
Positive (+1)
What is the charge of a neutron?
Neutral (0)
What is the relative mass of a proton?
1 (same as neutron)
What determines the size of an atom?
The volume of the orbit of its electrons
What is the mass of an electron?
Practically 0
What is the charge of an atom?
Neutral - the number of protons and electrons is equal, cancelling each other out
How does an ion differ from an atom?
An ion has an overall charge because the number of protons isn’t equal to the number of electrons, while an atom is neutral
What does the atomic number tell us?
How many protons are in an atom (the smaller number)
What does the mass number tell us?
The total number of protons and neutrons in an atom (the bigger number)
What defines which element an atom is?
The number of protons in the nucleus
What is an element?
A substance which contains only atoms with the same number of protons
What are isotopes?
Different forms of the same element, with the SAME number of PROTONS but a DIFFERENT number of NEUTRONS (they have the same atomic number but a different mass number)
What is relative atomic mass?
The average mass taking into account the different masses and abundance’s of all isotopes that make up an element
What is the formula for relative atomic mass?
relative atomic mass = (sum of (isotope abundance*isotope mass number))/(sum of abundances of all the isotopes)
What are compounds?
Substances formed of +2 elements, the atoms of each being in a fixed proportion throughout the compound, where the atoms are held together by chemical bonds
What is involved in making bonds between atoms?
Electrons - their being given away, shared or taken - the nucleus isn’t affected
What is needed to separate original elements of a compound?
A chemical reaction
Which kinds of elements is a compound consisting of ions made out of?
A metal and a non-metal
What is ionic bonding?
The attraction of oppositely charged ions formed by a compound containing metals and non-metals
What is the electron exchange that takes place in ionic bonding?
The metal atoms lose electrons (forming positive ions) which the non-metal atoms gain (forming negative ions)
What does a compound of non-metals consist of?
Molecules