Atom and Moles Flashcards
The description and order of different representations of the atom.
- Solid Sphere model: Just a solid sphere
- Plum pudding model: Solid positive sphere with negative electrons within the sphere
- Nuclear Model: Positive nucleus, negative electrons just around the nucleus
- Planetary Model: Positive nucleus made of protons and neutrons, negative electrons in fixed energy levels (shells) around the nucleus
- Quantum Model: Positive nucleus made of protons and neutrons, “clouds” of negative electrons around the nucleus in different energy levels
Who made each representation of the atom?
Solid Sphere Model: John Dalton
Plum Pudding Model: J.J. Thompson
Nuclear Model: Ernest Rutherford
Planetary model: Niels Bohr
Quantum Model: Erwin Schrodinger
What is an isotope?
An atom of an element with the same number of protons, but a different number of neutrons
What is Relative Atomic Mass?
the mean mass of all the naturally occuring atoms in an element compared with the mass of 1/12 of carbon-12
What is Relative Isotopic Mass?
the mean mass of an isotope compared with 1/12 of the mass of carbon-12
What are the typical charges of each group on the Periodic Table?
Group 1: 1+
Group 2: 2+
Group 3: 3+
Group 4: no typical charge
Group 5: 3-
Group 6: 2-
Group 7: 1-
Group 0: 0
What is Avagadro’s Constant?
The molecules/atoms in 1 mole of a substance
What value is Avagadro’s Constant?
6.02*10²³
What is the symbol for molar mass?
g mol⁻¹
What is an emprical formula?
The simplest whole number ratio of atoms of each element in a compound
What is a molecular formula?
the number and type of every atom in a molecule
What is the concentration of a solution?
how many moles of a substance is dissolved in the volume of liquid it is in
What is the symbol for concentration?
moldm⁻³
How many cm³ are in 1 dm³?
1000cm³
What value is the ideal gas constant?
8.314 J mol⁻¹ K⁻¹
What is % yeild of a chemical reaction?
The percentage of the real yeild compared to the theoretical yeild
What is the atom economy of a chemcial reaction?
The molar mass of the desired products compared to the total molar mass of all the products
What is a hydrated salt?
Salt that contains water within its structure
What is an anhydrous salt?
Salt that doesn’t contain any water within its structure
What is water of crystalisation?
The water trapped within the crystal structure of a hydrated salt
What is a standard solution?
A solution that has a known exact concentration
What is a titration?
Adding a solution of known concentration to a solution of unknown concentration to determin the unknown solution’s concentration
What is the formulae for the number of moles?
Moles = mass (g) /molar mass (g mol⁻¹)
Moles = number of particles / Avagadro’s constant
What is the formula for the ideal gas equation?
pV = nRT
p = Pressure (Pa)
V = Volume = (m³)
n = number of moles (mol)
R = ideal gas constant (J mol⁻¹ K⁻¹)
What is the formula for the concentration of a solution?
Concentration (mol dm⁻³) = moles (mol) / volume (dm³)
What is the formula for the % yeild of a reaction?
% yeild = actual mass of products (g) / theoretical mass of products (g) * 100
What is the formula for the % atom economy of a reaction?
% atom economy = molar mass of desired product (g mol⁻¹) / molar mass of total products (g mol⁻¹) * 100
