Answer:
8 kg mass
Explanation:
As we can see in the image the weight of mass 8 kgs has a large surface area as compared to the surface area of other masses. In general, it has been observed that a wide surface area has more surface particle for heat conduction. Hence, the rate of heat transfer is directly proportional to the surface area of heat conducting surface. Thus, the larger the surface area, the faster is the rate of heat conduction.
Hence, weight of mass 8Kg wil transfer heat a fast rate.
Answer:

Explanation:
The given reactions are:
PbCl2(aq)⇌Pb2+(aq)+2Cl−(aq) 
AgCl(aq)⇌Ag+(aq)+Cl−(aq) 
Required reaction is:
PbCl2(aq)+2Ag+(aq)⇌2AgCl(aq)+Pb2+(aq)

To convert boiling water to steam, that would involve heat of vaporization. The heat of vaporization for water at atmospheric conditions is: ΔHvap = <span>2260 J/g.
Molar mass of water = 18 g/mol
Q = m</span>ΔHvap = (1.50 mol water)(18 g/mol)(<span>2260 J/g) = 61,020 J
Time = Q/Rate = (61,020 J)(1 s/20 J) = 3051 seconds
In order to express the answer in three significant units, let's convert that to minutes.
Time = 3051 s * 1min/30 s = <em>102 min</em></span>