The average atomic mass of Sn is 118.71 g/mol
the percentage of heaviest Sn is 5.80%
the given mass of Sn is 82g
The total moles of Sn will be = mass / atomic mass = 82/118.71=0.691
Total atoms of Sn in 82g = 
the percentage of heaviest Sn is 5.80%
So the total atoms of
= 5.80% X 
Total atoms of
=
atoms
the mass of
will be = 
Answer:
A
Explanation:
A chemical change is when a new substance is created, which often has its own chemical properties, so A is the correct answer.
Answer:-
2747.7 Cal mol -1
Explanation:-
Molar heat of Fusion is defined as the amount of heat necessary to melt (or freeze) 1 mole of a substance at its melting point.
Atomic mass of Iron = 55.845 g mol-1
Mass of Iron = 200 g
Number of moles of Iron = 200 g / (55.845 g mol-)
= 3.581 moles
Heat released = 9840 Cal
Molar heat of Fusion = Heat released / Number of moles
= 9840 Cal / 3.581 moles
= 2747.7 Cal mol -1
The greenhouse effect increases the temperature of the Earth by trapping
heat in our atmosphere. This keeps the temperature of the Earth higher
than it would be if direct heating by the Sun was the only source of
warming.
When the sunlight reaches the surface of the Earth, some of it is absorbed
which warms the ground and some bounces back to space as heat. Greenhouse gases that are in the atmosphere absorb and then redirect some of this heat back towards the Earth.