Monthly Archives: December 2017

Chemistry SAT class homework, Week of Dec. 11, 2017

For average weighted atomic mass shown in the Periodic table, prove the numerical value of Na is the same with either unit of AMU (atomic mass unit) or grams/mole. You must show your calculations in detail with units written for each step.

1 AMU = 1.66054e-24 grams


By definition, 12.0000 AMU equals the mass of 1 Carbon-12 atom (isotope).

The standard scientific unit used to quantify the amount of a substance in macroscopic quantities is the mole (symbol: mol), which is defined arbitrarily by the scientific community as the amount of a substance which has as many atoms or molecules as there are atoms in 12 grams of the carbon isotope C-12. The number of atoms in a mole is called Avogadro’s number, the value of which is approximately 6.022140857(74)×1023 mol−1.

Chemistry SAT class homework, Week of Dec. 04, 2017

Count number of Sigma and Pi bonds in the C6H6 molecule(s) below.

Determine if it is polar or nonpolar molecule.