Chemistry review #3

One "mole" in chemistry represents the number:

• 2.63 x 10^22

• 6.02 x 10^23

• 4.10 x 10^23

• 0.06 x 10^23

How many grams are in 1 mol of the compound?

Round to 2 decimal points

• 11.62 g/mol

• 12.011 g/mol

• 13.02 g/mol

• 15.04 g/mol

What is the Empirical formula of a compound with

0.783g of Carbon, 0.196g of Hydrogen, and 0.521g of Oxygen

• CHO

What does the empirical formula tell us?

• The actual number of atoms in a compound

• The concentration of a compound

• the molar mass of a compound

• The lowest ratio of each element in a compound

The molecular formula tells us

• The actual number of the atoms in each element in a compound

• the lowest ratio of atoms of each element in a compound

• All possible multiples of an empirical formula

• the concentration of that compound in a solution

What is the percent composition of the element Na in NaOH?

• 40%

• 3%

• 57%

• 33%

• Sn = 52%

  O = 48%

• Sn = 79%

  O = 21%

• Sn = 24%

  O = 76%

• Sn = 85%

  O = 15%

• 41%

• 54%

• 5%

• 46%

What is the empirical formula of a compound which contains 89.14% Au and 10.80% of O

Au = 196.967 g/mol

O = 15.999 g/mol

• AuO