Questions: Decide whether each pair of elements in the table below will form an ionic compound. If they will, write the empirical formula of the compound formed in the space provided. element #1 element #2 Forms ionic compound? empirical formula of ionic compound --- --- --- --- rubidium Iodine yes fluorine sodium yes oxygen bromine yes oxygen sodium yes

Solution Steps

• Rubidium (Rb) is an alkali metal and typically forms a \( +1 \) charge.
• Iodine (I) is a halogen and typically forms a \( -1 \) charge.
• Since they have opposite charges, they will form an ionic compound.

• The charges balance each other out in a 1:1 ratio.
• The empirical formula is \( \text{RbI} \).

• Fluorine (F) is a halogen and typically forms a \( -1 \) charge.
• Sodium (Na) is an alkali metal and typically forms a \( +1 \) charge.
• Since they have opposite charges, they will form an ionic compound.

• The charges balance each other out in a 1:1 ratio.
• The empirical formula is \( \text{NaF} \).

• Oxygen (O) typically forms a \( -2 \) charge.
• Bromine (Br) is a halogen and typically forms a \( -1 \) charge.
• Both elements are non-metals and do not form an ionic compound with each other.

• Oxygen (O) typically forms a \( -2 \) charge.
• Sodium (Na) is an alkali metal and typically forms a \( +1 \) charge.
• Since they have opposite charges, they will form an ionic compound.

• Two sodium ions (\( \text{Na}^+ \)) are needed to balance one oxide ion (\( \text{O}^{2-} \)).
• The empirical formula is \( \text{Na}_2\text{O} \).

Final Answer