Question

a calcium atom has type here valence electrons. it needs to transfer type here electrons to oxygen to have a full outer shell. an oxygen atom has type here valence electrons. it needs to accept type here electrons from calcium to have a full outer shell.

Explanation:

Step1: Determine calcium's valence electrons

Calcium is in group 2, so it has 2 valence electrons.

Step2: Determine electrons calcium transfers to oxygen

Calcium wants a full outer - shell. It gives away its 2 valence electrons to oxygen.

Step3: Determine oxygen's valence electrons

Oxygen is in group 16, so it has 6 valence electrons.

Step4: Determine electrons oxygen accepts from calcium

Oxygen needs 2 more electrons to have a full outer - shell (8 electrons in the outer shell), so it accepts 2 electrons from calcium.

Answer:

2; 2; 6; 2