if k2O, SrO, and Al2O3 are all correct formulas, predict the formulas for the oxides of Rb, Mg, & Ga.
i think the answers are Rb2O, MgO,& Ga2O3 but im not sure why
All are correct. Why?
K2O means K is +1, Rb is in the same column so we predict +1 for it too; therefore, Rb is Rb2O. Same reasoning for Mg and Ga.
To predict the formulas for the oxides of Rb (rubidium), Mg (magnesium), and Ga (gallium), we need to consider the charges of each respective element.
1. Rubidium (Rb): Rubidium belongs to Group 1 of the periodic table. Elements in Group 1, also known as the alkali metals, have a charge of +1.
2. Magnesium (Mg): Magnesium belongs to Group 2 of the periodic table. Elements in Group 2, also known as the alkaline earth metals, have a charge of +2.
3. Gallium (Ga): Gallium belongs to Group 13 of the periodic table. Elements in Group 13, also known as the boron group, have a charge of +3.
To form an ionic compound, the sum of the charges of the cations (positive ions) and anions (negative ions) must be zero.
Now, let's predict the formulas for the oxides:
1. Rb (Rubidium): Since rubidium has a charge of +1, it needs to balance with an oxide ion, which has a charge of -2. So, we would need two rubidium ions to balance the charge of one oxide ion. Therefore, the formula for the oxide of rubidium is Rb2O.
2. Mg (Magnesium): Since magnesium has a charge of +2, it only needs one oxide ion to balance its charge. Therefore, the formula for the oxide of magnesium is MgO.
3. Ga (Gallium): Since gallium has a charge of +3, it needs two oxide ions to balance its charge. Therefore, the formula for the oxide of gallium is Ga2O3.
Therefore, your predictions are correct! The formulas for the oxides of Rb, Mg, and Ga are Rb2O, MgO, and Ga2O3, respectively.