Module 2, IQ1 Flashcards
(11 cards)
The law of conservation of mass
During any chemical reaction matter neither is created or destroyed. Mass is conserved from reactants to products.
The number of atoms of each element in a chemical reaction remains unchanged.
Precipitate reaction
When a solid is formed from two liquids.
The mass remains the same. The products equal the reactants.
E>G AgNO3 + NaCl –> AgCl +NaNo3
Carbonate
Creates hydrogen gas. Can be found through a limewater test.
Closed system
Where a quantity or a series of quantities cannot enter or leave the system in a closed system the mass of the system cannot change.
Open system
A quantity or series of quantities that can enter or leave the system. The mass of the system can change overtime.
Stoichiometry
The Quantitative relationship between the amounts of substances involved in a chemical reaction. It involves using a balanced chemical equation to calculate the reactants and products.
Balanced chemical equation
When the number of atoms involved in the reactants and products is equal.
The mole concept
The mole as a number of atoms contained in exactly 12.og of carbon-12. Carbon-12 is chosen due to its stability, physical state and abundance.
A mol containes 6.022 x10^23 it can be atoms, molecules, ions.
The number is also known as Avogadro’s number.
The relationship is N(Number of particles)= n (Number of moles) x Na(Avogadro’s constant)
Formula weight and molecular weight
Sum of the atomic weights,.
Moles and Mass
The atomic weight of any element in grams is one mole of the element.
Formula is
m
n= M
m over M
n= number of moles
m= mass (g)
M= molar mass
Moles and gas volumes
Quantities of gases are measured by volume and not gas
pV=nRT
p= pressure of gas (kPa)
V= volume of gas (L)
n= number of moles
R= 8.314kPA (Universal gas constant)
T= absolute temperature. (K)
K= Celsius + 273.15
