The repeating group of a crystal is called the
a. nucleus.
b. unit cell.
c. net.
d. crystal system.

Classify this reaction: 2al+n2-> aln.

Ican determine the molar mass of an element by looking on the under the atomic mass for the element. for example the molar mass of phosphorus is 30.974 grams/mole. avogadro’s number tells me the amount of representative particles in 1 mole of any substance. this means 12.011 gram sample of carbon and a 32.0 gram sample of sulfur have the same number of atoms.

Is a pencil falling to the floor anon contact force, a force, or a contact force