Which one of the following order is correct for the first ionisation energies of the elements?
B <Be <N < O
Be <B <N < O
B <Be <O <N
B <O <Be <N
The cubic unit cell of a metal (molar mass = 63.55 g mol-1) has an edge length of 362 pm. Its density is 8. 92 g cm-3. The type of unit cell is
primitive
face centred
body centred
end centred
B.
face centred
The equilibrium constant for the given reaction is 100.
What is the equilibrium constant for the reaction given below?
10
1
0.1
0.01
20 mL of 0.1 M acetic acid is mixed with 50 mL of potassium acetate. Ka of acetic acid = 1.8 x 10-5 at 27C. Calculate concentration of potassium acetate if pH of the mixture is 4.8.
0.1 M
0.04 M
0.4 M
0.02 M
Match the following.
List I | List II | ||
(A) | Flespar | (I) | [Ag3SbS3] |
(B) | Asbestos | (II) | Al2O3.H2O |
(C) | Pyrargyrite | (III) | MgSO4.H2O |
(D) | Diaspore | (IV) | KAlSi3O8 |
(V) | CaMg3(SiO3)4 |
(A) (B) (C) (D)
IV V II I
(A) (B) (C) (D)
IV V I II
(A) (B) (C) (D)
IV I III II
(A) (B) (C) (D)
II V IV I
The concentration of an organic compound in chloroform is 6.15 g per 100 mL of solution. A portion of this solution in a 5 cm polarimeter tube causes an observed rotation of -1.2°. What is the specific rotation of the compound?
+12
-3.9
-39
+61.5
Fluorine reacts with dilute NaOH and forms a gaseous. product A. The bond angle in the molecule of A is
104°40'
103°
107°
109°28'