To find the chemical formula for the ionic compound formed by magnesium (Mg) and phosphorus (P) using the crisscross method, follow these steps:
1. Determine the charges of the ions:
- Magnesium (Mg) typically has a +2 charge because it tends to lose two electrons to achieve a full outer shell.
- Phosphorus (P) typically has a -3 charge because it tends to gain three electrons to achieve a full outer shell.
2. Write the symbols for the ions with their charges:
- Mg^2+ for magnesium
- P^3- for phosphorus
3. Use the crisscross method to balance the charges:
- Take the absolute value of the charge on the phosphorus ion (3) and use it as the subscript for the magnesium ion.
- Take the absolute value of the charge on the magnesium ion (2) and use it as the subscript for the phosphorus ion.
This gives you:
- Mg_3
- P_2
4. Write the chemical formula by combining the ions with their respective subscripts:
- The resulting formula is Mg_3P_2.
Therefore, the correct formula for the ionic compound formed by magnesium and phosphorus is [tex]\( Mg_3P_2 \)[/tex].
So the correct answer is:
B. [tex]\( Mg_3P_2 \)[/tex]
