JEE Advance - Chemistry (1987)

• 1

  sp² hybrid orbitals have equal s and p character.

  Відповідь

  (B)

  FALSE
• 2

  The brown ring complex compound is formulated as [Fe(H₂O)₅(NO)⁺]SO₄. The oxidation state of iron is

  Відповідь

  (A)

  1
• 3

  (i) What is the weight of sodium bromate and molarity pf solution necessary to prepare 85.5 ml of 0.672 B solution when the half-cell reaction is
  
  $$BrO_3^- + 6H^+ + 6e^- \to $$ $$Br^- + 3H_2O$$
  
  (ii) What would be the weight as well as molarity if the half-cell reaction is:
  
  $$2BrO_3^- + 12H^+ + 10e^- \to$$ $$Br_2 \,+ 6H_2O$$

  Відповідь

  (A)

  (i) 1.446 gm, 0.112 M; (ii) 1.7532 g, 0.1344 M
• 4

  In group IA, of alkali metals, the ionisation potential decreases on moving down the group. Therefore, lithium is a strongest reducing agent

  Відповідь

  (B)

  FALSE
• 5

  The first ionisation potential in electron volts of nitrogen and oxygen atoms are respectively given by

  Відповідь

  (A)

  14.6, 13.6
• 6

  Atomic radii of fluorine and neon in Angstrom units are respectively given by

  Відповідь

  (A)

  0.72, 1.60
• 7

  The electronegativity of the following elements increases in the order

  Відповідь

  (C)

  Si, P, C, N
• 8

  In benzene, carbon uses all the three p-orbitals for hybridisation.

  Відповідь

  (B)

  FALSE
• 9

  Hydrogen bond is maximum in

  Відповідь

  (A)

  Ethanol
• 10

  The value of PV for 5.6 litres of an ideal gas is ________ RT, at NTP.

  Відповідь

  0.25
• 11

  A spherical balloon of 21 cm diameter is to be filled up with hydrogen at N.T.P from a cylinder containing the gas at 20 atmospheres at 27^oC. If the cylinder can hold 2.82 litres of water, calculate the number of balloons that can be filled up.

  Відповідь

  10
• 12

  Sodium when burnt in excess of oxygen gives sodium oxide.

  Відповідь

  (B)

  FALSE
• 13

  The metallic lustre exhibited by sodium is explained by

  Відповідь

  (B)

  oscillation of loose electrons
• 14

  Give reasons of the following :
  Magnesium oxide is used for the lining of steel making furnace.

  Відповідь

  (C)

  Magnesium oxide is basic in nature and reacts with acidic impurities of the steel making process.
• 15

  Give reasons of the following:
  Why is sodium chloride added during electrolysis of fused anhydrous magnesium chloride?

  Відповідь

  (C)

  To increase the electrical conductivity of the electrolyte.
• 16

  The IUPAC name of the compound
  CH₂ = CH $$-$$ CH(CH₃)₂

  Відповідь

  (B)

  3-methylbut-1-ene
• 17

  An unknown compound of carbon, hydrogen and oxygen contains 69.77% carbon and 11.63% hydrogen and has a molecular weight of 86. It does not reduce Fehling solution, but forms a bisulphite addition compound and gives a positive iodoform test. What are the possible structures?

  Відповідь

  (A)