Chemical equations Flashcards
What is a compound
A substance that is made up of two or more different elements combined together chemically
What is always formed when a chemical reaction occours
a new substance is always formed when a chemical reaction occours
What are the starting substances called
Reactants
What are the substances formed called
Products
What is the law of conservation mass
stated that the total mass of the products of a chemical euqation is the same as the total mass of the rectants
What is the law of conservtion matter
states that in any chemical reaction, mass is neither created or destroyed but merely changes from one form into another
What is a balanced equation
total number of atoms of each element on the left hand side of the equation is equal to the nuber of toms on the right hand side of the equation,
Describe the test for chloride atoms
Cloride (Cl-)
add Silver nitrate (AgNo3)
white percipate formed
Ag+ +cl- = AgCl ↓
addammonia (NH3)
white percipate dissapears
Describe the test for Sulphate (SO4 2-) and Sulfite (SO3 2-)
Sulphate (SO4 2-) Sulfite (SO3 2-)
addBarium Chloride (BaCl2)
white ppt formes
Ba2+ + SO4 2- = BaSO4 ↓
Ba2+ + So3 2- = BaSO 3 ↓
addHydrocloric acid (HCl)
BaSO4 + HCl = no reaction
BaSO3 + HCl = white ppt disseapears
Test for the presense of carbonate (CO3 2-) and Hydrogen Carbonate (HCO3-)
To carbonate (CO3 2-) and Hydrogen Carbonate (HCO3-)
add Hydrocloric acid (HCl)
a vigours fizzing is observed
CO3 2- + 2H+ = CO2 + H2O
HCO3- + H+ = Co2 + H2O
addMagnesium sulfate (Mgso4)
Mg2+ 2HCO3 = MgCO3 ↓ white ppt formes
Mg2+ + 2HCO3 = Mg(HCO3)2 no ppt formed
test for the presence of Nitrate ions (NO3-)
Dissolve nitrate salt in dissolved water
add fresh Iron (II) sulfate (FeSO4)
add Concentrated Sulphuric acid (H2SO4) slowly down the side using a dropper
Formation of a brown ring at the junction of the liquids
Test for the presense of Phosphate ions(PO4 3-)
Dissolve phosphate salt in deionised water
add ammonium molybdate
addconcentrated nitric acid slowly down the sides using a dropper
Place in warm water
yellow ppt formes
