Chemical Foemulae and Equation
Card 1: State the meaning of chemical formula.
A chemical formula is a symbol use to show the type of elements and quantity of element that present in a chemical substance.
The formula shows that
Card 2: State the meaning of empirical formula.
An empirical formula is a chemical formula that gives the simplest whole-number ratio of each element in a molecule.
The ratio of carbon:hydrogen:oxygen = 6:12:6
Therefore, the empirical formula of glucose is CH2O
Calculate the empirical formula of a compound consisting of 85.7% C and 14.3% H. (Relative atomic mass: Carbon=12; Hydrogen = 1)
The simplest ration of Carbon and Hydrogen is 1:2. Therfore the empirical formula = CH2
Card 3: State the meaning of molecular formula.
A molecular formula is a chemical formula that shows the actual number of each element in a molecule.
Card 4: Constructing Chemical Formula
Constructing Chemical Formula
2 Requirements to form the formula of an ionic compound
1 Magnesium ion combine with 2 chloride ions to form 1 magnesium chloride formula.
Card 5: State the meaning of chemical Equation.
A chemical equation is a precise description of a chemical reaction.
2 sodium atoms react with 2 water molecules to form 2 sodium hydroxide molecule and 1 hydrogen molecule.
Equantion: 2Na + 2H2O ---> 2NaOH + H2
Reactants: Na and H2O