Writing formulas for polyatomic compounds

Work through this activity and complete the notes in the spaces in the guided notes for this section. The answers to the practice questions from the Powerpoint are on the slide following the problems.

Multiple Choice

Why is it important to use parentheses when writing formulas for polyatomic compounds with multiple subscripts?

• To indicate the presence of more than one polyatomic ion

• To make the formula look more organized

• To separate cations and anions

• To show the charge of the ion

Open Ended

How do you determine the correct formula for a compound formed between a metal and a polyatomic ion?

Multiple Choice

Which of the following are correct formulas for the compounds formed from the following pairs? 1) Strontium and sulfide 2) Rubidium and phosphate 3) Gold (III) and nitrate 4) Antimony (III) and phosphite

• SrSO3, Rb3PO4, AuNO3, SbPO3

• SrS, RbPO4, Au(NO3)3, Sb(PO3)3

• SrSO4, Rb3PO3, Au(NO2)3, SbPO4

• SrS2, Rb2PO4, Au(NO3)2, Sb3PO3

Fill in the Blanks

Fill in the blank: The name of the cation in a polyatomic compound is the name of the

element.

Multiple Choice

Which of the following is the correct name for the compound NaNO2?

• Sodium nitrite

• Sodium nitrate

• Sodium nitride

• Sodium dioxide

Dropdown

What is the name of this compound?
MgSO₄​

Select answer

Match

Match the following

• sulfate

• phosphate

• sulfide

• carbonate

• ammonium

SO₄ ^-2

PO₄ ^-3

S^-2

CO₃ ^-2

NH₄ ⁺¹

• SO₄ ^-2

• PO₄ ^-3

• S^-2

• CO₃ ^-2

• NH₄ ⁺¹