C3 Atoms, Elements Compounds Flashcards
Which group are the noble gases in the periodic table
Group 8
Why are the noble gases very unreactive
They have a full outershell, meaning they have the most stable electronic configuration
What is the most stable electron configuration
A full outer shell of electrons. Atoms react in order to gain a full outer shell of electron, so that they become more stable
Why are alloys harder than pure metals
Atoms in pure metals are in arranged uniform rows which can easily slide over each other making them malleable. Alloys contain different sized atoms which disort layers and are unable to slide. This makes it hard
Alloy
A mixture containing metals and another element
Covalent bond
A bond formed when two non metals share a pair of electrons
Isotopes
Atoms of an element with the same number of protons but a different number of neutrons. Ie same atomic number but different mass number
How are ions formed
Postive ions form when an atom loses electrons. Negative ions form when an atom gains electrons
What are ions
Atoms or groups of atoms with a positive or negative charge
What does atomic number represent
The number of protons in an atomic nucleus
What are cations ans anions
Cation-positive ion
Anion-negative ion
What types of elements are ionic bonds formed between
Between metals and non metals.
-Metals lose electrons to form positive ions.
- Non metals gain electrons to become negative ions.
Why do elements in the same group have similar chemical properties
Cuz they have the same number of electrons in the outer shell which determines how they react
How are elements arranged in the modern periodic table
In order of increasing atomic number. Elements with similar properties are in the same column
What does the mass of an atom mean?
The total number of protons and neutrons found in the nucleus of an atom
Why do atoms contain equal number of protons and electrons
Atoms are stable with no overall charge. There must be an equal number for the charges to balance
What are the relative charges of protons, neutrons and electrons
Proton: +1
Neutron: 0
Electron: -1
What does period(row) tell you about all the elements in that period
They have same number of electron shells. All elements in peiod 4 have 4 electron shells.