The value of Planck's constant is 6.63 x 10-34 Js. The speed of light is 3 x 1017 nms-1. Which value is closest to the wavelength in nanometer of a quantum of light with frequency of 6 x 1015 s-1?
10
25
50
75
What is the maximum numbers of electrons that can be associated with the following set of quantum numbers? n = 3, l = 1 and m =-1.
10
6
4
2
Based on equation certain conclusions are written. Which of them is not correct?
The negative sign in equation simply means that the energy of electron bound to the nucleus is lower than it would be if the electrons were at the infinite distance from the nucleus.
Larger the value of n, the larger is the orbit radius
Equation can be used to calculate the change in energy when the electron changes orbit.
For n = 1 the electron has a more negative energy than it does for n = 6 which means that the electron is more loosely bound in the smallest allowed orbit.
How many grams of concentrated nitric acid solution should be used to prepare 250 mL of 2.0M HNO3 ? The concentrated acid is 70% HNO3.
45.0 g conc. HNO3
90.0 g con. HNO3
70.0 g conc. HNO3
54.0 g conc. HNO3
Dipole-induced dipole interactions are present in which of the following pairs?
H2O and alcohol
Cl2 and CCl4
HCl and He atoms
SiF4 and He atoms
An excess of AgNO3 is added to 100 mL of a 0.01 M solution of dichlorotetraaquachromium (III) chloride. The number of moles of AgCl precipitate would be
0.001
0.002
0.003
0.01
A.
0.001
The formula of dichlorotetraqua chromium (lll) chloride is [Cr(H2O)4Cl2] Cl.
On ionisation it generates only one Cl- ion
One mole of Cl- ions react with on only 1 mole of AgNO3, molecule to produce 1 mole of AgCl.
.:. 1 mmol or 1 x 10-3 mole reacts with AgNO3 to give AgCl
=