Answer : The mass of the water in two significant figures is, 
Explanation :
In this case the heat given by the hot body is equal to the heat taken by the cold body.


where,
= specific heat of iron metal = 
= specific heat of water = 
= mass of iron metal = 32.3 g
= mass of water = ?
= final temperature of mixture = 
= initial temperature of iron metal = 
= initial temperature of water = 
Now put all the given values in the above formula, we get


Therefore, the mass of the water in two significant figures is, 
The Beer-Lambert law states that A = E*c*l where A is absorbance, E is the molar absorbance coeffecient, c is concentration and l is path length. Therefore the absorbance is directly proportional to concentration, and by increasing the concentration by a factor of 3, absorbance will increase by a factor of 3 giving A = 1.584
Answer:
b) The molecule has a molecular weight under 200 g/mole
Explanation:
The molecule has a molecular weight under 200 g/mole is the primary requirement for a molecule to be analyzed by Gas Chromatography.
The chemical change can occur can be find if you mix the two solids in one direction
Answer:
Option D. Iron and sulfur react to form iron sulfide
Explanation:
Reaction of iron with sulphur is a chemical property and not a physical property.