Converting Moles and Atoms in Chemistry

This video tutorial explains how to convert between moles and atoms using Avogadro's number. It covers examples involving zinc, nitrogen gas, copper, oxygen gas, magnesium phosphate, and aluminum sulfate. The tutorial emphasizes understanding molecular structures and chemical formulas to accurately perform conversions.

What is Avogadro's number used for in chemistry?

• To measure temperature

• To calculate the speed of light

• To convert moles to atoms and vice versa

• To determine the pH of a solution

How many atoms are in 5 moles of zinc?

• 5.022 x 10^23 atoms

• 1.204 x 10^24 atoms

• 6.022 x 10^23 atoms

• 3.011 x 10^24 atoms

What is the molecular formula for nitrogen gas?

• N

• NH3

• N2

• NO2

How many atoms are in 8 moles of nitrogen gas?

• 4.8 x 10^24 atoms

• 9.635 x 10^24 atoms

• 1.204 x 10^25 atoms

• 6.022 x 10^23 atoms

What is the first step in converting atoms to moles?

• Divide by Avogadro's number

• Subtract Avogadro's number

• Multiply by Avogadro's number

• Add Avogadro's number

How many moles of copper are equivalent to 8 x 10^24 copper atoms?

• 13.28 moles

• 8.4 moles

• 10.5 moles

• 6.022 moles

What is the extra step when converting oxygen atoms to moles of oxygen gas?

• Divide by 2

• Multiply by 2

• Add 2

• Subtract 2

How many moles of O2 are in 4.3 x 10^25 oxygen atoms?

• 25.6 moles

• 50.2 moles

• 35.7 moles

• 71.4 moles

What is the chemical formula for magnesium phosphate?

• Mg2(PO4)3

• Mg3(PO4)2

• Mg(PO4)2

• MgPO4

How many atoms are in one formula unit of aluminum sulfate?

• 15 atoms

• 17 atoms

• 20 atoms

• 12 atoms