Gen 1 - Stochiometry Flashcards
What is a molecule ?
The smallest unit of a compound that presents the properties of that compound.
What is the empirical formula of a compound ?
The simplest whole number ratio between the numbers of atoms of different elements that make up the compound.
What is the molecular formula of a compound ?
The number of the different atoms that make up a molecule
What is Avogadro’s number ?
The number of atoms in 12g of the most abundant carbon isotope.
Why do we need Avogadro’s Number ?
Large numbers of molecules need to be observed in reactions to bring microscopic chemical reactions to our macroscopic scale.
How do you calculate moles of an element or compound ?
What is the difference between the atomic weight of an element, and the mass of a single atom ?
Atomic weights are dimensionless numbers based on Carbon-12 as the reference standard Isotope. The mass of a single atom can be measured experimentally (!)
What is an Isotope of an element ?
An atom of an element with the same number of protons but a different number of neutrons.
Define atomic weight
The weight in grams of a mole of atoms
Define molecular weight
The weight in grams of a mole of molecules
How would you calculate % yield ?
How would you calculate theoretical yield ?
Theoretical yield is the calculated amound of product that can be predicted from a balanced chemical equation.
Give two examples of double replacement reactions
- Precipiation
- Acid-Base neutralisation
Define Oxidation
- An increase in Oxidation number
OR - Loss of one or more electrons
(Oxidation Is Loss)
Define Reduction
- Decrease in Oxidation number
OR - Gain of one or more electrons
(Reduction Is Gain)
What is the oxidation number of an Ion ?
In monatomic ions, the oxidation number of the element that makes up the ions is equal to the charge of the ion.
