Given that the pressure, temperature and area of effusion is constant, the rate of effusion is inversely proportional to the square root of the molecular mass of the gas.
Mr Oxygen = 32
Mr Argon = 40
Effusion Oxygen = 1/√32
Effusion Argon = 1/√40
Effusion Oxygen / Effusion Argon = √(40) / √(32)
=√(40/32) = √(5/4) = 1.19
Thus, Oxygen will effuse 1.19 times faster than Argon. The second option is correct.
Answer:
The answer is:
(a) 
(b) NaCl
(c) 0.211 g
Explanation:
Given:
The mass of NaCl,
= 0.0860 g
The molar mass of NaCl,
= 58.44 g/mol
The volume of
,
= 30.0 ml
or,
= 0.030 L
Molarity of
,
= 0.050 M
Moles of NaCl will be:
= 
= 
= 
now,
Moles of
will be:



(a)
The reaction is:
⇒ 
(b)
1 mole of NaCl react with,
= 1 mol of 
0.0015 mol
needs,
= 
Available mol of NaCl < needed amount of NaCl
So,
The limiting reagent is "NaCl".
(c)
The precipitate formed,
= 
= 