Be sure to answer all parts. write the formula for the following ionic compounds: (a) potassium oxide (b) iron(iii) sulfide (containing the felt ion) (c) cobalt(i) sulfate (containing the cotion and so, ion) o type here to search

Explanation:

(a) potassium oxide

Potassium is the element of group 1 and oxygen is the element of group 16. The most common valency of potassium and oxygen are 1 and 2 respectively.

So, the ionic compound formed:

K (Cation)        O (Anion)

1                       2

Interchange of the valency, So,

K₂O

(b) iron(III) sulfide

Iron is a d block element and sulfur is the element of group 16. The most common valency of sulfur is 2. The valency of iron is 3 which is written in roman in the name.

So, the ionic compound formed:

Fe (Cation)        S (Anion)    

3                        2

Interchange of the valency, So,

Fe₂S₃

(c) cobalt(I) sulfate

Cobalt is a d block element. The valency of cobalt is 1 which is written in roman in the name. Sulfate is an anion which has formula of SO₄²⁻ .

So, the ionic compound formed:

Co (Cation)     SO₄

1                      2

Interchange of the valency, So,

Co₂SO₄

6.4 cm (max) - 25 cm (min)

substituting a hydrogen atom with a halogen in a hydrocarbon:

- the single bond remains single. a is wrong.

- the bond with hydrogen is as strong as with a halogen. c is wrong

- a hydrocarbon is saturated if there is no double bond. we do not know that so d is wrong.

- carbon will always have four valence electrons. e is wrong.

by elimination, the correct answer is b. the boiling point of the new compound increases.