Mercury and Bromine are liquid at room temperature.
Answer:
d)Cells 1 and 2
Explanation:
In a voltaic cell, oxidation occurs at the anode and reduction occurs at the cathode. The half cell that function as anode or cathode in a voltaic cell depends strictly on the reduction potential of the metal ion/metal system in that half cell.
Examining the reduction potentials of the various metal ion/metal systems in the three half cells;
Cu= +0.34 V
Ni= -0.25 V
Zn= -0.76 V
Fe(Fe2+)= -0.44 V
Hence only Zn2+ has a more negative reduction potential than Fe2+. The more negative the reduction potential, the greater the tendency of the system to function as the anode. Thus iron half cell will function as anode in cells 1&2 as explained in the argument above.
Answer: The freezing point of 3.46 gram of a compound X in 160 gram of benzene is 
Explanation:
The relation of density and molar mass is:
where
d = density = 3.27 g/ L
P = pressure of the gas = 773 torr = 1.02 atm (760 torr = 1atm)
M = molar mass of the gas = ?
T = temperature of the gas = 
R = gas constant = 
The relation of depression in freezing point with molality:
= depression in freezing point = 
= 
= freezing point constant = 5.1
m = molality = 
Thus the freezing point of 3.46 gram of a compound X in 160 gram of benzene is
