Chemistry Lecture - The Mole and Molar Mass

Flashcards covering the concept of the mole, molar mass calculations, and Avogadro's number based on the lecture transcript.

Avogadro's number

The number of units in one mole of a substance, which is $6.022 \times 10^{23}$.

$$N_A$$

The symbol used to represent Avogadro's number.

Amaedo Avogadro

The Italian chemist after whom Avogadro's number is named.

Reacting Species Ratio Principle

The rule that increasing the number of reacting atoms or molecules will not change the ratio in which these are reacting or are being formed.

Gram to Atomic Mass Unit (amu) conversion

According to the lecture notes, $1.00\,g = 6.022 \times 10^{23}\,amu$.

Molar mass calculation of Carbon in example

$2 \times 6.022 \times 10^{23} \times (12.0\,amu) = 24.00\,g$ carbon atoms.

Molar mass calculation of Oxygen molecules in example

$6.022 \times 10^{23} \times (32.0\,amu) = 32.00\,g$ oxygen molecules.

Molar mass calculation of Carbon Monoxide in example

$2 \times 6.022 \times 10^{23} \times (28.0\,amu) = 2 \times 28.00\,g$ carbon monoxide molecules.

Reaction mass ratio (2C + O2 → 2CO)

The simplified mass ratio in the laboratory for this equation is $24\,g$ of Carbon + $32\,g$ of Oxygen yielding $56\,g$ of Carbon Monoxide.

Significance of Avogadro's number

It has an immense significance in Chemistry for converting between atomic/molecular scales and convenient laboratory masses.