Tell me which names are incorrect and why look at the following formulas and corresponding names and tell me which names are incorrect and why. cacl2 calcium chloride cu2o copper (ii) oxide pbs2 lead (ii) sulfide

Explanation:

The nomenclature of ionic compounds is given by:

1. Positive is written first.  And if the metal atom has various oxidation states then its oxidation state is to be mentioned in brackets with help of roman numbers

2. The negative ion is written next and a suffix is added at the end of the negative ion. The suffix written is '-ide'.

1.) : Calcium chloride  (Correct)

In the given compound, calcium has oxidation state of +2 and chlorine has oxidation state of -1.The name is correct.

2.) : Copper (II) oxide   (Incorrect)

In the given compound,copper has the oxidation state of +1 and oxygen has oxidation state of -2.So ,the correct name will be Copper (I) oxide.

3.) : Lead (II) sulfide   (Incorrect)

In the given compound, lead has the oxidation state of +4 and sulfur has oxidation state of -2. So ,the correct name will be Lead (IV) sulfide.

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

the answer is b & c i believe : )