Chemical Symbols and Mole Concepts

The video tutorial explains how to find the number of atoms in magnesium oxide (MgO). It begins by identifying the elements in MgO, magnesium (Mg) and oxygen (O), and explains that if no subscript is present, it is assumed to be one. Thus, MgO has one magnesium atom and one oxygen atom, totaling two atoms. The video further explains how to calculate the number of atoms in one mole of MgO using Avogadro's number, multiplying the number of atoms by 6.02 x 10^23. This method is applied to both magnesium and oxygen atoms. The tutorial concludes with a brief sign-off from Dr. B.

What are the element symbols for magnesium and oxygen in MgO?

• M and O

• Mg and O

• Mn and O

• Mg and Ox

How many atoms are there in a single molecule of MgO?

• One

• Three

• Two

• Four

If no number is written after the element symbol in a chemical formula, what is assumed?

• Zero

• Two

• One

• Three

What is Avogadro's number used for in chemistry?

• To determine pressure

• To measure temperature

• To calculate volume

• To count atoms in a mole

How many atoms are there in one mole of MgO?

• 6.02 x 10^25

• 6.02 x 10^23

• 6.02 x 10^22

• 6.02 x 10^24