Strontium and Nitrate Compounds

The video tutorial explains how to write the chemical formula for strontium nitrate. It begins by identifying the symbols for strontium (Sr) and nitrate (NO3), noting that nitrate is a polyatomic ion with a charge of 1-. Strontium, found in group 2 of the periodic table, has a 2+ charge. To form a neutral compound, two nitrate ions are needed to balance the charge of one strontium ion. The final formula is Sr(NO3)2, with the charges balancing to zero. The tutorial emphasizes understanding ionic charges and balancing them to form neutral compounds.

What is the symbol for strontium when writing its chemical formula?

• St

• Sr

• Sn

• Sm

Which of the following is a polyatomic ion?

• O2

• Cl

• H2O

• NO3

What is the ionic charge of the nitrate ion?

• 1+

• 2+

• 2-

• 1-

In which group of the periodic table is strontium found?

• Group 3

• Group 1

• Group 2

• Group 4

Why do we need two nitrate ions to balance the charge of one strontium ion?

• Because nitrate has a 2+ charge

• Because strontium has a 1- charge

• Because nitrate has a 1- charge and strontium has a 2+ charge

• Because strontium has a 1+ charge

What is the purpose of using parentheses in the formula for strontium nitrate?

• To indicate the charge of the compound

• To separate different elements

• To show the number of strontium ions

• To indicate the presence of a polyatomic ion

What is the final chemical formula for strontium nitrate?

• SrNO3

• Sr(NO3)2

• Sr2(NO3)2

• Sr2(NO3)

How do the charges of strontium and nitrate ions add up in the compound?

• They add up to 2+

• They add up to 1+

• They add up to 0

• They add up to 1-