Sec 3NA Chemistry Revision Quiz

1. 1. What is the chemical formula of hydroxide ion?

2. 2. What is the chemical formula of nitrate ion?

3. 3. What is the chemical formula of phosphate ion?

4. 4. What is the chemical formula of carbonate ion?

5. 5. What is the chemical formula of ammonium ion?

6. 6. What is the chemical formula of sulfate ion?

8. 7. Define valency of an element.

• Charge without its sign

• Number of electrons needed to gain or lose to attain 8 valence electrons

• Number of electrons needed to share to attain 8 valence electrons

• Number of electrons needed to gain / lose / share to attain a stable noble gas electronic configuration

9. 8. Define valency of an ion.

• Charge of the ion with its sign

• Charge of the ion without its sign

• Number of electrons needed to gain/lose/share to attain a stable noble gas electronic configuration

• Number of electrons needed to share to attain 8 valence electrons

7. 9. What does "IV" mean in terms of Roman numerals?

• 3

• 4

• 5

• Intravenous

10. 10. What is the valency of the calcium element?