ChemGoals

You can practice MCQ's here and ask if you have doubt in any question:

1. How many valence electrons does an oxygen atom have?
(a) 2
(b) 6
(c) 8
(d) 16

2. Fluorine atoms tend to...?...when they form chemical compounds with metals.
(a) lose electrons
(b) gain electrons
(c) neither lose nor gain electrons...they usually share electrons equally with metals.
(d) Fluorine atoms do not form compounds with other atoms...fluorine is an inert gas.

3. The identity of an element is determined by...
(a) the number of its protons.
(b) the number of its neutrons.
(c) the number of its electrons.
(d) its atomic mass.

4. The probability area that best represents the shape of an atomic 3p orbital is...

5. Which of the following is the correct electron-dot formula for water?

6. Which of the following is the correct electron-dot formula for carbon dioxide?

7. Which of the following represents the correct formula for aluminum oxide?
(a) AlO
(b) Al2O3
(c) AlO2
(d) Al2O

8. Which of the bonds, shown by the dash, has the greatest polarity?
(a) H-Cl
(b) H-NH2
(c) H-OH
(d) H-SH

9. What is the major attraction between water molecules in the solid physical state?
(a) dipole-dipole interactions
(b) electrostatic interactions between charged atoms
(c) hydrogen-bonds
(d) physical entanglement of the molecules

10. Which of the following is the correct name for NaHCO3?
(a) sodium hydrogen carbonate
(b) sodium acetate
(c) nitrogen hydrogen carbonate
(d) sodium hydrogen carbon trioxide

11. Which of the following electron configurations represents the electron configuration for a magnesium cation...Mg2+?
(a) 1s22s22p63s2
(b) 1s22s22p63s23p2
(c) 1s22s22p6
(d) 1s22s22p4

12. What would be the volume in liters of 640 g of oil if the density of the oil is 0.8 g/mL?
(a) 800 liters
(b) 0.8 liter
(c) 512 liters
(d) 0.5 liters

13. What is the formal charge of the oxygen atom of the following compound?
(a) +3
(b) +1
(c) -2
(d) -3

14. How many milligrams are in 0.2 decigrams?
(a) 20 milligrams
(b) 2000 milligrams
(c) 0.002 milligram
(d) 0.00002 milligram

15. What happens when a fluorine atom becomes a fluoride ion in a chemical reaction?
(a) A proton is gained by the nucleus.
(b) A proton is lost by the nucleus.
(c) An electron is lost from one of the outer orbitals.
(d) An electron is added to one of the outer orbitals.

16. Which of the following orbital box diagrams represents silicon, which has 14 electrons?

Figure enclosed here!

Can anyone tell the reason?