Q21. What are covalent bonds? What type of elements are they usually between and

why do they form?/nNa

sodium atom

leone electroach to form

[Na]

odum ion

chlorine atom

[CAT

chlorine ion

[Na] [:CI:]

sodium chloride/nsodium chloride

Q22. From the page lonic Bonds (click on blue link for information), what is an

example of an ionic compound with a 1:2 ratio?

Q23. Illustrate the following ionic substances. You can do this as electron dot

diagrams, verbal descriptions, or pictorial diagrams. There is a link to upload these

images in the directions at the end of the lesson.

1. LICI

2. Cao

3. KBr

4. Srl,

5. MgCh/nQ24. Which type of substance is each of the following? Explain your choice.

1. NaCl

2. CaF₂

3. H₂

4. Ar

5. SO₂

6. C₂H₂O

7. Cu

8. 0₂

9. Potassium lodide:/nQ25. Indicate whether each of the following is a physical or chemical change and

explain your choice.