Molar Mass and Chemical Formulas flashcard

These flashcards cover key concepts related to molar mass, chemical formulas, and related calculations from the lecture.

What is the definition of a mole in chemistry?

A mole (mol) is the chemist's 'dozen' and is equal to 6.022 x 10^23 particles.

How is molar mass defined?

Molar mass is the mass of 1 mole of an element, expressed in grams per mole (g/mol).

What is the relationship between atomic mass and molar mass?

An element's molar mass in grams per mole is numerically equal to its atomic mass in atomic mass units (amu).

What is Avogadro's number?

Avogadro's number is 6.022 x 10^23 particles, which represents the number of atoms in 1 mole.

How do you calculate the molar mass of a compound?

The molar mass is calculated by summing the atomic masses of all the atoms in its chemical formula.

What is the formula mass?

Formula mass is the sum of the atomic masses of all the atoms represented in its chemical formula.

How can you convert between grams and moles of a substance?

Use the molar mass to convert between grams and moles; 1 mole of a substance corresponds to its molar mass in grams.

What is mass percent composition in a compound?

Mass percent composition is the percentage of an element's mass relative to the total mass of the compound.

How do you find the empirical formula from experimental data?

Convert the masses of elements to moles, write a pseudoformula, and divide by the smallest subscript.

What is the difference between empirical and molecular formulas?

The molecular formula is a whole-number multiple of the empirical formula.

What are the steps to determine empirical formulas from percent composition?

Assume 100 g total mass, convert percentages to grams, convert grams to moles, and then write the pseudoformula.

What is the formula for calculating mass percent of an element?

Mass percent of element X = (number of X in compound × molar mass of X) / (molar mass of compound) × 100%.

How do you calculate grams of an element in a compound from mass percent?

Multiply the mass percent by the total mass of the compound and divide by 100.

How can combustion analysis be used to find empirical formulas?

Weigh the products, calculate moles of carbon and hydrogen, and determine oxygen by subtraction from the original mass.