Chemical Compounds and Their Composition

The video tutorial explains how to count atoms in chemical formulas, using examples like barium nitrate, sodium chloride, and magnesium bicarbonate. It covers the role of subscripts, parentheses, and coefficients in determining the number of atoms in compounds and molecules.

What is the charge on the nitrate ion in the barium nitrate compound?

• Positive monatomic

• Positive polyatomic

• Negative polyatomic

• Neutral

In the compound sodium chloride, what does the absence of subscripts indicate?

• The elements are in a gaseous state

• There is one atom of each element

• There are two atoms of each element

• The compound is unstable

How many sodium atoms are present in sodium oxide?

• One

• Two

• Three

• Four

In beryllium phosphide, how many phosphorus atoms are present?

• Three

• Two

• One

• Four

For calcium chlorate, how many total oxygen atoms are present?

• Six

• Twelve

• Three

• Nine

What does a coefficient of five in front of NaCl indicate?

• Five molecules of water

• Five NaCl compounds

• Five chlorine atoms

• Five sodium atoms

In carbon dioxide with a coefficient of three, how many total oxygen atoms are there?

• Eight

• Four

• Two

• Six

How many total magnesium atoms are present in four magnesium bicarbonate compounds?

• One

• Three

• Four

• Two

In magnesium bicarbonate, how many total hydrogen atoms are there when the coefficient is four?

• Four

• Eight

• Twelve

• Sixteen

How many total oxygen atoms are present in four magnesium bicarbonate compounds?

• Twelve

• Thirty

• Eighteen

• Twenty-four