Question

determine the number of electrons lost or gained when each atom forms an ion.
be □ □ electrons.
se □ □ electrons.
i □ □ electrons.
p □ □ electrons.

Explanation:

Step1: Analyze Beryllium (Be)

Beryllium is in Group 2 of the periodic table. Atoms in Group 2 typically lose 2 electrons to achieve a stable electron configuration (like a noble gas). So Be loses 2 electrons.

Step2: Analyze Selenium (Se)

Selenium is in Group 16 (or 6A). Atoms in Group 16 typically gain 2 electrons to achieve a stable electron configuration (since they have 6 valence electrons and need 2 more to reach 8, the octet rule). So Se gains 2 electrons.

Step3: Analyze Iodine (I)

Iodine is in Group 17 (or 7A). Atoms in Group 17 typically gain 1 electron to achieve a stable electron configuration (they have 7 valence electrons and need 1 more to reach 8). So I gains 1 electron.

Step4: Analyze Phosphorus (P)

Phosphorus is in Group 15 (or 5A). Atoms in Group 15 typically gain 3 electrons to achieve a stable electron configuration (they have 5 valence electrons and need 3 more to reach 8). So P gains 3 electrons.

Answer:

Be: loses 2 electrons.
Se: gains 2 electrons.
I: gains 1 electron.
P: gains 3 electrons.