A radioactive sample is emitting 64 times radiations than non-hazardous limit .If its half-life is 2 hours , after what time it becomes non- hazardous ?
16 h
10 h
12 h
8 h
Inert gases are mixed in iodine vapours. Then there are _____ between them.
H-bonding
van der Waals forces
electrostatic forces
metallic bonds
B.
van der Waals forces
When inert gases are mixed in iodine vapours, they have van der Waals forces between them. These forces are strong but are only short range forces, for e.g. for surface of neutral molecules or inert gases. It increases with the size or surface are of the molecule. In halogens, it increases as F2 > Cl2 < Br2 < I2.
Critical temperatures for A, B, C and D gases are 25°C, 10°C, -80°C and 15°C respectively. Which gas will be liquefied more easily?
A
B
C
D
Assertion : If H2 and Cl2 enclosed separately in the same vessel exert pressure of 100 and 200 mm respectively, their mixture in the same vessel at the same temperature will exert a pressure of 300 mm.
Reason : Dalton's law of partial pressures states that total pressure is the sum of partial pressures.
If both assertion and reason are true and reason is the correct explanation of assertion.
If both assertion and reason are true but reason is not the correct explanation of assertion.
If assertion is true but reason is false.
If both assertion and reason are false.
If the r.m.s. speed of a gaseous molecule is x m/sec at a pressure P atm , then what will be the r.m.s. speed at a pressure 2P atm and constant temperature ?
x
2x
4x
x/4
The solution obtained by adding water to alcohol, shows :
+ve deviation from Raoult's law
ideal behaviour
-ve deviation from Raoult's law
application of Henry's law