2.3 - Formulae and equations Flashcards
What do atoms of metals on the left of the periodic table do?
They lose electrons to form cations /positive ions
What do atoms of non-metals on the right of the periodic table do?
They gain electrons to form anions / negative ions
What metals can form several ions with different charges?
Transition metals mainly e.g. copper (I) and copper (II)
What do binary compounds contain?
How do you name binary compound?
Two elements only
To name binary compound =, use name of first element but change ending of second element name to -ide
What are polyatomic ions?
An ion that contains atoms of more than 1 element bonded together
Rules to write formulae for ions (2)
Overall charge is 0 is Ionic charges must balance
sum of positive charges = sum of negative charges
Which elements exist as diatomic molecules?
H2 N2 O2 F2 Cl2 Br2 I2
contain 2 atoms bonded together
What other elements other than diatomic molecules exist as small molecules?
Phosphorus and sulfur
What is the formula unit?
for ionic compounds: the formula worked out from ionic charges that is used in equations
What is the charge and symbol of a nitrite ion?
NO2 -
What is the charge and symbol of a hydrogencarbonate ion?
HCO3-
What is the charge and symbol of a manganate (VII) (permanganate) ion?
MnO4-
What is the charge and symbol of a sulfite ion?
SO3 2-
What is the charge and symbol of a dichromate (VI) ion?
Cr2O7 2-
What is the charge and symbol of a phosphate ion?
PO4 3-
