Etiket Arşivleri: Example
Law of Conservation of Mass
The total mass of substances present after a chemical reaction (rxn) is the same as the total mass of substances before the rxn.
Example: 0.455 g of Mg is burned in 2.315 g oxygen. The product is magnesium oxide (MgO). After the rxn the mass of unreacted oxygen is 2.015 g. What mass of MgO was produced ?
Average Atomic Mass
The atomic mass (weight) of an element is the average of the atomic masses, weighted according to the naturally occuring abundances of the isotopes of the element.
Example: What is the atomic weight of Mg ? The element consists of 78.70 % atoms (mass = 23.99 u), 10.13 % atoms (mass = 24.99 u) and 11.17 % atoms (mass = 25.98 u).
Example: What quantity of heat is associated with the complete combustion of 1 kg of sucrose ?