7.2 Molar Mass

7.2 Molar Mass

• Benadryl is used to treat arthritis.
• The formula of Naproxen is C14H14O3.

• The formula for Benadryl is C17H21NO.

• Naproxen is used to treat arthritis.

• The chemical formula of a substance can be used to calculate its mass.

• Even on the most accurate balance, a single atom or molecule is too small to weigh.

• It takes a lot of atoms to make a substance.
• A few sips of water contains Avogadro's number of water molecule.
• In the laboratory, we can use a balance to weigh out Avogadro's number of particles.

• When we weigh out the number of grams equal to the element's mass, we are left with 6.02 atoms.
• Carbon has an atomic mass of 12.01.
• A mole of carbon atoms has a mass of 12.01.

• To get 1 mole of carbon atoms, we need to weigh out 12.01 g of carbon.
• The atomic mass of carbon is found by looking at it.

• If you want to determine the molar mass of a compound, you have to add the results from Sample Problem 7.3 to the formula.
• In this text, we round the mass of an element to the hundredths place or use at least four significant figures for calculations.

• Sulfur, S, iron, Fe, salt, NaCl, and K2Cr2O7 are 1-mole samples.

• The molar mass of Li2CO3 is used to treat bipolar disorder.