Welcome to your CHM TEST MBBS
1.
How many grams of NaOH are needed to prepare 125mL of 0.2M solution of NaOH?
2.
An Oil drop has 6.39×10^−19C change. Find out the number of electrons in this oil drop.
3.
The oil drop experiment by R.A. Millikan was performed to find________.
4.
Which of the solution is the most concentrated?
5.
According to Milikan, electronegativity is defined as
6.
What is the mole fraction of sodium hydroxide in a 20% by mass, solution of sodium hydroxide?
7.
How many significant figures are in 100.0
8.
Calculate the molarity of a solution after 1.70liters of 2.06M solution is diluted to 2.50liters?
9.
In 1932, the neutron was discovered by a scientist by bombarding beryllium with radiation. What is the name of the scientist and what radiation did he bombard beryllium with?
10.
A hypothetical element with an atomic weight of 65.0 amu consists of just two isotopes. One of the isotopes consists of atoms having a mass of 64.23 amu; the other of 65.32 amu. What is the percent natural abundance of the heavier isotope?
11.
Y = A + B - C. If A = 5.79 ± 0.03, B = 15.19 ± 0.02 and C = 21.609 ± 0.004. Calculate the standard error in Y
12.
A compound has a composition of 40% Sulphur and 60% Oxygen by mass. What is the empirical formula of this compound? ( S=32, O=16))
13.
We know that most of an atom’s mass is in its nucleus; the mass of an electron compared to mass of the lightest nucleus is ___
14.
The maximum number of electrons that can be accommodated in a sublevel for which "ml" = ±1 and 0 is
15.
What is the percentage yield of water if 0.95g of water is obtained when 29.0g of butane is burned in excess oxygen?
16.
Rutherford carried out experiments in which a beam of alpha particles was directed at a thin piece of metal foil. From these experiments he concluded that:
17.
When an electron do transition from n = 4 to n=2, the emitted line of spectrum will be:
18.
Calculate the de-Broglie's wavelength if an electron travels at the speed of light. (Given that Planck's constant, h is 6.626 × 10-³⁴Js)
19.
Nuclides with the same atomic mass are called
20.
What is the molality of a 20% by mass, solution of sodium hydroxide?