Amount of substance (Chapter 2) (CHEMISTRY)
What is the SI unit for amount of substance?
Mole
What is the formula to calculate the number of moles?
n = P/V
Avogadro's number represents the number of particles in one _______ of a substance.
mole
Which of the following is a common unit to express the amount of substance?
All of the above
The number of atoms or molecules in one mole of a substance is called __________.
Avogadro's constant
In chemical reactions, the stoichiometric coefficients represent the __________ ratio of reactants and products.
molar
According to the ideal gas law, the amount of substance can be calculated using the equation ________.
n = PV/RT
Which of the following represents the molar mass of a substance?
The mass of one mole of the substance
Which of the following statements is true regarding the amount of substance?
The amount of substance is directly proportional to the number of particles.
What is the formula for Ar?
average mass of one molecule x 12/ mass of one atom of 12C
What is the formula for Mr?
average mass of one molecule x 12/ mass of one atom of 12C
What is the relative formula mass used for?
Ionic compounds since they don't exist as single molecules
What is the Avogadro Constant?
The number of atoms in 12g of carbon-12
What is the equation for the number of moles?
moles = mass/mass of 1 mole
What does the concentration of a solution tell us?
The amount of a solute within a known volume of a solution.
What is Boyle's law?
The product of pressure and volume is a constant as long as the temperature remains constant.
What is Charles' law?
The volume is proportional to the temperature as long as the pressure remains constant.
What is Guy-Lussacs' law?
The pressure is proportional to the temperature as long as the volume remains constant.
What is the ideal gas equation?
pressure(Pa) x volume(m3) = number of moles(n) x gas constant (J K-1 mol-1) x temperature (K)
What is the gas constant?
8.31 J K-1 mol-1
What is the equation for the number of moles?
number of moles = mass of element/mass of 1 mol of the element
How do you find the number of units of the empirical formula in the molecular formula?
Divide the relative molecular mass by the relative mass of the empirical formula.
What is the stoichiometry of the reaction?
The ratio in which the reactants react and the products produced, in whole numbers.
Equation for atom economy
(mass of desired product/total mass of reactants) x 100
Equation for the yield of a chemical reaction
(the number of moles of a specified product/ theoretical maximum number of moles of the product) x 100%