A 10 ml sample of hydroxylamine solution was Diluted to 1 litre. 50 ml of this diluted solution was boiled with an excess of iron (III) solution. The resulting solution required 12 ml of 0.02 M KMnO4 solution for complete oxidation of iron (II). Calculate the weight of hydroxylamine in one litre of the original solution. (H = 1, N = 14, O = 16, K =39, Mn = 55, Fe = 56)
پاسخ دهید
(D)
39.6 g/l
4
The mass of a hydrogen atom is ______ kg.
پاسخ دهید
(B)
1.673 × 10-27
5
Isotopes of an element differ in the number of ______ in their nuclei.
پاسخ دهید
(C)
neutrons
6
When there are two electrons in the same orbital, they have _____ spins.
پاسخ دهید
(B)
antiparallel
7
The outer electronic configuration of the ground state chromium atom is 3d4 4s2
پاسخ دهید
(B)
FALSE
8
Calculate the wavelength in Angstrom of the photon that is emitted when an electron in the Bohr orbit, n = 2 returns to the orbit, n = 1 in the hydrogen atom. The ionization potential of the ground state hydrogen atom is 2.17 $$\times$$ 10-11 erg per atom.
پاسخ دهید
(C)
1216 Å
9
The element with the highest first ionization potential is
پاسخ دهید
(C)
nitrogen
10
There are ______ $$\pi$$ bonds in a nitrogen molecule.
پاسخ دهید
2
11
____ hybrid orbitals of nitrogen atom are involved in the formation of ammonium ion.
پاسخ دهید
(C)
sp3
12
The ion that is isoelectronic with CO is
پاسخ دهید
(A)
CN-
13
Among the following, the molecule that is linear is
پاسخ دهید
(A)
CO2
14
The compound with no dipole moment is
پاسخ دهید
(B)
carbon tetrachloride
15
Helium atom is two times heavier than a hydrogen molecule. At 298 K, the average kinetic energy of a helium atom is
پاسخ دهید
(C)
same as that of a hydrogen molecule
16
At room temparature, ammonia gas at 1 atm pressure and hydrogen chloride gas at P atm pressure are allowed to effuse through identical pin holes from opposite ends of a glass tube of one metre length and of uniform cross-section. Ammonium chloride is first formed at a distance of 60 cm from the end through which HCL gas is sent in. What is the value of P?
پاسخ دهید
(C)
4.83 atm
17
MgCl2.6H2O on heating give anhydrous MgCl2
پاسخ دهید
(B)
FALSE
18
How will you prepare bleaching powder from slaked lime.
پاسخ دهید
(A)
By treating slaked lime with chlorine gas.
19
Write down the balanced equations for the reaction when:
An alkaline solution of potassium ferricyanide is reacted with hydrogen peroxide.
