Quantitative Chemistry Flashcards
FOLLOW TEST AND REVISE FROM IT. ALSO, REVISE FROM MOCK TOPIC PAPER.
PLEASE.
What does the law of conservation of mass state?
That no atoms are lost or made during a chemical reaction so the mass of the products equals the mass of reactants.
How can chemical reactions be represented?
By symbol equations which are balanced if the number of atoms of each element involved on both sides of the equation.
What is the relative formulae mass (Mr) of a compound?
The sum of the relative masses of the atoms in the numbers shown in the formula.
How are chemical amounts measured in?
In moles. The symbol for the unit mole is mol.
What is the Avogadro constant?
The number of atoms, molecules or ions in a mole of given substance. The value of Avogadro constant is 6.02x10²³ per mole.
What is meant by the term concentration?
The amount of a substance dissolved in a certain volume of solution.
What is meant by the term end point?
The point in a titration where the reaction is complete and titration should stop.
What is the formulae for percentage yield?
Actual yield ÷ theoretical yield × ¹ºº.
What is a pipette?
A glass tube used to measure accurate volumes of liquids.
What is meant by the term yield?
The mass of product that a chemical reaction produces.
What is the formulae to find mass (g)?
› number of moles x Ar
OR
› number of moles x Mr
What is the formulae to find concentration (g/dm³)?
Amount of solute (g) ÷ volume of solution (dm³).
What is the formulae to find the percentage mass of an element in a compound?
Percentage mass of an element in a compound = Aᵣ x number or atoms of that element / Mᵣ of the compound x 100
What is a balanced equation?
A symbol equation with the same number of atoms of each element on both sides.
