CHEM QUIZ

• A and D

• B and C

• B and C

• A and B

Which of the following represent a molecular formula and its empirical formula?

• molecular formula = CH₄ and empirical formula = CH₂

• molecular formula = C₅H₁₀ and empirical formula = CH₂

• molecular formula = C₂H₆ and empirical formula = C₂H₄

• molecular formula = C₃H₆ and empirical formula = CH₃

Given the unbalanced redox equation below:

MnO₄^- + I^- -> I₂ + Mn²⁺ (acidic medium)

What is the stoichiometric coefficient number for Mn²⁺ after the

reaction is balanced in acidic medium?

• 1

• 2

• 3

• 4

What is the mole fraction of urea, (NH₂)₂CO in a solution by

dissolving 4.45 mole urea in 250.0 g of water?

• 0.0300

• 0.0521

• 0.2426

• 0.7920

Given the combustion reaction below:

C₅H₁₂ + 8O₂ → 5CO₂ + 6H₂O

If the initial reactants C₅H₁₂ and O₂ are having 2 and 8 moles

respectively, how many moles of C₅H₁₂ remained when the reaction

completes?

• 0

• 1

• 2

• 3

Select the correct arrangement for the configuration below according

to Aufbau’s Principle.

• 1s < 1p < 2s < 2p < 3s < 4p < 3p

• 1s < 2s < 2p < 3s < 4d < 3p < 3d

• 1s < 2p < 2s < 3p < 3s < 4d < 3p

• 1s < 2s < 2p < 3s < 3p < 4s < 3d

An electron located at n=5, emits a photon of wavelength 1281 nm.

What is the initial energy level for this movement?

[Given R_H = 1.097 x 107 m^-1]

• 4

• 3

• 2

• 1

Which of the following set of quantum numbers is not allowed ?

• n = 2 ; l = 2 ; m = -1 ; s= + 1/2

• n = 3 ; l = 2 ; m = +1 ; s= - 1/2

• n = 3 ; l = 1 ; m = 0 ; s= + 1/2

• n = 1 ; l = 0 ; m = 0 ; s= - 1/2

Given the set of quantum numbers for the highest energy electron in

atom J is:

(3, 1, 0, +1/2)

What is the most stable ion for J?

• J⁺

• J²⁺

• J³⁺

• J⁴⁺

Given the K_p for this reaction at 340^OC is 4.00. Calculate K_c at the same temperature.

NH₃ (g) + HCl (g) ⇋ NH₄Cl(g)

• 2.01 X 10²

• 3.20 X 10⁷

• 1.01 X 10⁴

• 1.01 X 10⁷