MOLAR MASS
What is a mole?
The mole is an amount unit similar to familiar units like a pair, or a dozen, or a gross, etc. It provides a specific measure of the number of atoms or molecules in a sample of matter.
What is an Empirical Formula?
The lowest whole number ratio of the elements a compound.
What is a Molecular Formula?
A compound that gives the total number of atoms of each element in each molecule of a substance.
The left hand side of a chemical equation is known as what?
The Reactants
What is Stoichiometry?
A key concept in chemistry that involves the calculation of reactants and products in chemical reactions.
What is Avagadro's number?
6.022 x 1023
A substance contains 40.0% sulfur and 60.0% oxygen by mass. Determine the empirical formula of the substance
SO3
What is the first thing you need to do to calculate the molecular formula?
Calculate the Empirical Formula
The right hand side of a chemical equation is known as what?
The Products
What is Percent Yield
It is the ratio of the actual yield to the theoretical yield, expressed as a percentage.
What is the molar mass of CaCl2
110.98 g/mol
What is the Empirical Formula of C2H6O2
CH3O
A particular substance has a molar mass of 180 g/mol and an empirical formula of CH2O. What is the molecular formula?
C6H12O6
Balance the following chemical equation: P4 + H2 --> PH3
P4 + 6H2 --> 4PH3
What is theoretical yield?
How much of the product should be formed based on stoichiometry.
What is the molar mass of lithium chloride?
42.4 g/mol
A compound contains 27.3% carbon (C), 72.7% oxygen (O) by mass. What is the empirical formula of the compound?
CO2
A compound with the empirical formula P2O5 was found to have a molecular weight of 283.90 g/mol. What is the molecular formula for this compound?
P4O10
Balance CF4 + Br2 --> CBr4 + F2
CF4 + 2Br2 --> CBr4 + 2F2
What is actual yield?
The amount of product that is actually formed when the reaction is carried out in the laboratory.
Calculate the molar mass of Cr4(P2O7)3
729.8 g/mol
Elemental analysis of a hydrocarbon contained 4.185 g of C and 0.815 g of H. What is the empirical formula of this hydrocarbon?
C3H7
A compound was determined to have 1.18 g H and 18.8 g O. If the molar mass of the compound is 34.0 g/mol, find its empirical and molecular formulas.
Empirical: HO Molecular: H2O2
Balance AgBr + GaPO4 --> Ag3PO4 + GaBr3
3AgBr + GaPO4 --> Ag3PO4 + GaBr3
What is the theoretical yield of PH3 when 82.0g of H2 reacts with excess P4 in the equation P4 + 6H2 --> 4PH3
921.7 g