Y12 Mid-course revision

Which of the following statements is correct?

• Gay-Lussac's law states that at constant pressure the volume of a fixed mass of an ideal gas is directly proportional to its absolute temperature

• Temperatures are measured in celsius to calculate with gas laws

• Avogadro's law states that equal volumes of gases at the same temperature and pressure contain equal numbers of particles 

• Boyle's law states that at constant temperature, the pressure and volume of a fixed mass of an ideal gas are proportional to each other

The Hydrogen's emission spectrum's spectral lines lie on what region of the electromagnetic spectrum?

                   I. Infrared 

                   II. Visible Light

                   III. Ultraviolet 

• I and II

• I and III

• II and III

• I, II, and III

 Choose the accurate statements about catalyst:

I. Lowering the activation energy

II. Haber process to produce ammonia is catalyzed by iron

III. Contact process to produce sulfuric acid is catalyzed by platinum

• I and II only

• I and III only

• II and III only

• I, II and III

Which is the correct reaction mechanism?

2NO (g) + 2H2 (g)  → N2 (g) + 2H2O (g)

Rate expression: rate = k[NO]2[H2]

• Step 1: NO (g) + NO (g) --> N2O2 (g) slow

  Step 2: N2O2 (g) + H2(g) --> N2O (g) + H2O (g) fast

  Step 3: N2O (g) + H2(g) --> N2(g) + H2O(g) fast

• Step 1: NO (g) + NO (g) --> N2O2 (g) fast

  Step 2: N2O2 (g) + H2(g) --> N2O (g) + H2O (g) slow

  Step 3: N2O (g) + H2(g) --> N2(g) + H2O(g) fast

• Step 1: NO (g) + NO (g) --> N2O2 (g) fast

  Step 2: N2O2 (g) + H2(g) --> N2O (g) + H2O (g) fast

  Step 3: N2O (g) + H2(g) --> N2(g) + H2O(g) slow

• Step 1: NO (g) + H2 (g) -->NOH + H+ (g) fast

  Step 2: NOH (g) + H2(g) --> N2 (g) + H2O (g) slow

What is the mass of hydrogen gas that will be produced when 50g of magnesium reacts completely with excess hydrochloric acid according to the balanced chemical equation:

Mg + 2HCl → MgCl2 + H2?

• 1.68 g

• 1.12 g

• 0.56 g

• 2.24 g

Which of the following elements has the highest electronegativity?

• Na

• Mg

• Cl

• Br

Which compound has the shortest C–N bond?

• CH3NH2

• (CH3)3CNH2

• CH3CN

• CH3CHNH

What is the equilibrium constant expression for this reaction

Cu2+ + 4NH3 = [Cu (NH3) 4]2+

• [Cu (NH3) 4]2+/ [Cu]2+[NH]4

• [[Cu (NH3) 4]2+] / [Cu2+][NH]4

• 2[Cu (NH3)4] / 2[Cu] 4[NH3]

• D [[Cu(NH3)4]2+] / [Cu2+] [4NH3]

What is the unit for second order reaction?

• mol dm-3 s-1

• mol-2 dm-6 s-1

• mol-1 dm-3 s-1

• s-1