Compounds Formulae and Equations 2.1.2 Flashcards
What is the overall charge of an atom
0
What is an ion
An atom (or group of covalently bonded atoms) has either a positive or negative charge, where number of electrons is different to number of protons, because electrons have been lost or gained
What is a molecule
2 or more (non-metal) atoms covalently bonded (not ionically bonded) with no overall charge
What is an element
A substance containing only one type of atom with the same number of protons in the nucleus
What is a compound
Contains 2 or more types of elements chemically combined in a fixed proportion
What is the charge on a proton
+1
What is the charge on a neutron
0
What is the charge on an electron
-1
How is a negative ion formed
An atom (or group of covalently bonded atoms) gains electrons
How is a positive ion formed
An atom (or group of covalently bonded atoms) loses electrons
What is an ionic bond
Ions held together by the electrostatic force of attraction between positive and negative ions
What charge is usually on a metal ion
Positive
What charge is usually on a non-metal ion
Negative
What ending do you use on the name of a non metal ion which contains only one element
-ide
What are the formula of the 7 key ions :ammonium ,silver, zinc, nitrate, sulfate, carbonate, hydroxide
Ammonium= NH4 plus
Silver=Ag plus
Zinc=Zn 2 plus
Nitrate=NO3 minus
Sulphate=SO4 2 minus
Carbonate=CO3 2 minus
Hydroxide= OH minus
what are the formula of these molecules: ammonia, methane, chlorine, bromine, hydrogen
Ammonia=NH3
Methane= CH4
Chlorine=Cl2
Bromine= Br2
Hydrogen=H2
what is a covalent bond
Strong electrostatic force of attraction between a shared pair of electrons and the nuclei of the two bonded atoms
What type of bonding is usually between a metal and a non-metal
Ionic bonding
What type of bonding occurs between 2 non-metals
Covalent bonding
What is an atom
The smallest particle of an element that gives it its chemical properties. It contains a nucleus with protons (1+ charge) and neutrons ( 0 charge) surrounded by shells of electrons with a 1- charge
What is a group on the periodic table and what does it tell us
A vertical column in the periodic table, all the elements in the same group have the same number of outer shell electrons in an atom
What is an atomic number
The number of protons in the nucleus of an atom
What is the mass number
The sum of protons and neutrons in the nucleus
What is a cation
A positively charged ion with fewer electrons than protons (as it has lost electrons to another species)
What is an anion
A negatively charged ion with more electrons than protons (as it has gained electrons from another species)
What is a polyatomic ion
An ion containing more than one atom
What are lone pairs
An outer shell pair of electrons that is not involved in chemical bonding
What is ionic bonding
Strong electrostatic force of attraction between positive and negative ions
What is empirical formula
Shows the simplest whole number ratio of atoms of each element in a compound. (Formula of ionic compounds are always empirical formula)
What is molecular formula
Shows the actual number and type of atoms of each element in a molecule
What is dative covalent bond
A covalent bond in which the shared pair of electrons has been provided by one of the bonding atoms only
What is metallic bonding
Strong electrostatic force of attraction between the cations (positive ions) and delocalized electrons
Define acid
A species that releases/donates a proton ( H+ ions ) in aqueous solution
Define base
A species that accepts a proton ( H+ ions ) in aqueous solution, a compound that neutralizes the acid to form a salt
What is salt
The ionic compound formed from a reaction between an acid and a base
What are spectator ions
Spectator ions are ions that are
* Not changing state
* Not changing oxidation number
during a chemical reaction
What does a metal element do to become a cation
A metal element loses electrons from its outer shell to form a positive ion called a cation
Elements in group 1 loose how many electrons and what charge do they have and become as a result
Elements in group 1 loose 1 electron to form 1 + ion
Elements in group 2 loose how many electrons and what charge do they have and become as a result
Elements in group 2 loose 2 electrons from their outer shell to form a 2+ ion
Elements in group 3 loose how many electrons and what charge do they have and become as a result
Elements in group 3 loose 3 electrons from their outer shell to form a 3+ ion
What charge do the ions have from each group
Group 1
Group 2
Group 3
Group 1 = 1+
Group 2 = 2+
Group 3 =3+
Metal elements in group 4 usually loose how many electrons and give examples
Metal elements in group 4 usually only loose 2 electrons to form a 2+ ion
e.g. Pb 2plus and Sn 2 plus
How many electrons are lost from transition metals
Transition elements can loose different number of electrons to form different positive ions
How do you know how many electrons a transition metal has lost e.g. Iron (II)
The number of electrons lost is written in Roman Numerals in brackets after the metal
E.g. Iron (II) would be Fe 2 plus
Iron (III) would be Fe 3 plus
Is hydrogen a metal or non-metal
Non-metal
What charge does a non–metal form
A non-metal element gains electrons in its outer shell to form negative ions called anions
Elements in group 7 gain how many electrons and what charge do they have and become as a result
Elements in group 7 gain 1 electron to form a 1- ion e.g. Cl-
Elements in group 6 gain how many electrons and what charge do they have and become as a result
Elements in group 6 gain 2 electrons to form a 2- ion
e.g. O 2 minus
Elements in group 5 gain how many electrons and what charge do they have and become as a result
Elements in group 5 gain 3 electrons to form a 3 - ion
e.g. N 3 minus
What charge do the ions have from each group
Group 5
Group 6
Group 7
Group 5 = 3 minus
Group 6= 2 minus
Group 7= 1 minus
How do you determine the name of a cation
Name of metal (+ Roman numbers to show charge if transition metal)
How do you determine the name of the anion
Name of non-metal- but change ending to -ide
How is a giant ionic lattice formed
Oppositely charged ions attract each other and form a giant ionic lattice- cation + anion
In a giant ionic lattice what are bigger the cations or the anions
Negative anions are bigger than positive cations in a giant ionic lattice
What is the overall charge in an ionic compound
There is no overall charge in an ionic compound
True or False
The amount of positive charge must equal to the amount of negative charge in an ionic compound
True hence there is no overall charge on an ionic compound
What do ionic solids show
Formula shows the ratio of cations (+) to anions (-) and no charges are shown in the formula
Multiples of ions are represented by what
A subscript number after the ion