Chemistry 103 Quiz: Trivia Questions!

1. Write the formula between ionic compounds K and S?

KS2

K3S2

K2S

K2S3

2. Round 0.00758 to two significant figures.

0.0080

0.00750

0.0076

0.0075

3. The group 6A called?

Halogens

Noble gases

Alkali metal

Chalcogens

4. Convert 5 km/h to m/sec?

1.5 m/sec

1.37 m/sec

1.39 m/sec

2 m/sec

5. The charge of element Ra?

+1

-1

+2

Non of the above

6. Calculate the mass in gram of cube if density = 19.32 g/cm3 and the length of the cube is 2 cm.

154.56 g

155 g

154.1 g

156 g

7. What is the concentration M of Na+ in a solution by dissolving 23.4 g of Na2CO3 in 125.0 ml of solution? M.w(Na2CO3) = 106 g/mol

3.4 M

3.53 M

3.00 M

4.1 M

8. 6.5 grams of Al reacts with excess of Oxygen. How many grams of Al2O3 is formed ? ( M.W Al = 27 g/mol . M.W Al2O3 = 102 g/mol ) 4Al + 3O2 ——> 2Al2O3

11.2 g

12.1 g

12.24 g

13.35 g

9. How many Oxygen atoms are in 0.88 mol of C6H12O6? ( N.A = 6.02 *10^23 )

31*10^23

31.8*10^23

32*10^24

5.3*10^23

10. What is the molar mass Ba(OH)2 .8H2O?

281.4 g/mol

298.4 g/mol

299.5 g/mol

315.5 g/mol

11. When 5g of H2 and 5g of O2 were reacted, the yield of H2O was 87.9%. What is the actual yield of H2O? 2H2 + O2 ——> 2H2O

6.4 g

4.9 g

5.1 g

12.8 g

12. Which one of the following is a correct expression for molarity?

Mol solute / L solvent

Mol solute / ml solvent

Mmol solute / ml solution

Mmol solute / L solution

13. Carry out the following operation ( 4.02+5.612 ) ( 15.2-15.15 ) =

0.48

0.4

0.5

0.4816

14. 50.0 ml of water were added to 150 ml of 5.0 M H2SO4 solution, calculate the concentration of the solution.

3.3 M

3.5 M

4.00 M

3.75 M

15. Calculate the molarity of NaOH solution if 10.42 ml of this solution are needed to neutralize 25.00 ml of 0.2043 M oxalic acid ( H2C2O4) ?

1.500 M

0.9803 M

0.4902 M

0.2500 M