Chemistry - Chapter Five: Chemical Formulae, Equations and Calculations: Part One Flashcards
What is a coefficient?
A coefficient is the large number before a symbol that shows how many unjoined particles of a substance there are
What are the subscript numbers?
The subscript numbers show how many joined atoms of the substance there are
What are state symbols?
Symbols put after substances in brackets which show the state of that substance
What does the [s] symbol stand for in a formula?
Solid state
What does the [g] symbol stand for in a formula?
Gaseous state
What does the [l] symbol stand for in a formula?
Liquid state
What does the [aq] symbol stand for in a formula?
Aqueous state [dissolved in water]
What is the Carbon-12 Scale?
The Carbon-12 Scale is a measuring scale in which a Carbon-12 atom has a mass of exactly 12
What is Relative Formula Mass?
Relative Formula Mass [Mr] is the relative mass of a compound, taking into account all Relative Atomic Masses of the elements it is made up of
How does one work out Relative Formula Mass?
One calculates out relative Formula Mass by adding up the Relative Atomic Masses of each element involved, taking into account how much of that element there is
How does one work out percentage composition?
One calculates out percentage composition by dividing the Ar of the element whose percentage one is working out by the Mr
What is the mole?
A mole is a unit of amount of substance, like a dozen; it is equal to avogadro’s number of that substance
How does one calculate the mass of a mole of a substance?
One calculates the mass of one mole of a substance by calculating the Mr of the substance and attaching nthe units in grams
