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
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
Intermolecular hydrogen bonding is strongest in
methylamine
phenol
formaldehyde
methanol
D.
methanol
Methanol has strongest intermolecular hydrogen bonding because it has more -OH group.
---H - O(CH3) ----H - O(CH3) ----H - O(CH3)
With the increase of electronegativity and decrease in size of the atom to which hydrogen is colvalently linked, the strength of the hydrogen bond increases.