2. Which ions will form an ionic bond? A. two negative ions
B. a positive and a neutral atom
C. two positive ions
D. a positive ion and a negative ion

D. a positive ion and a negative ion

Explanation:

Ionic bonds is formed from the attraction of opposite full charges. So a positive ion and a negative ion will make a ionic bond (Similar to how Na+ and Cl- ions make salt - which is basically a crystal of ions bonded via ionic bonds)

you need to take a look at the periodic system in order to sort these elements into pairs that would most likely exhibit similar chemical properties. first, you need to find elements that are found in the same group (groups are vertical in the periodic system), and then to see whether they have the same valence number. if they meet these criteria, they will have similar properties.

the first pair: ne (neon) and kr (krypton), are noble gases found in group 8

the second pair: li (lithium) and k (potassium), found in group 1

the third pair: s (sulfur) and te (tellurium), found in group 6

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