Answer: Option (b) is the correct answer.
Explanation:
A change that does not lead to any difference in chemical composition of a substance is known as a physical change.
For example, shape, size, mass, volume, density, boiling point, etc of a substance are all physical properties.
Boiling of water is a physical change as it leads to conversion of liquid state of water into vapor state.
On the other hand, changes that lead to bring change in chemical composition of a substance is known as a chemical change.
For example, exploding dynamite, rotting cheese etc are all chemical changes.
Thus, we can conclude that the statement no, boiling water is a physical change is true when water is heated, bubbles form in the water. This evidence is not of a chemical reaction.
Answer:
2.52kg
Explanation:
80mm = 8 cm
0.15m = 15 cm
volume of the container = 10m × 8cm × 15cm
= 1200 cubic centimetres
mass = density × volume
= 2.1 × 1200
= 2520g
2520/ 1000
= 2.52kilograms
Boiling point of cyclohexane at 620 mm hg?
Standard atmospheric pressure is 760 mm Hg. Boiling point at 760 mm= 80.74˚C
A liquid boils when its vapor pressure is equal to the atmospheric pressure. The vapor pressure of a liquid is proportional the absolute temperature of the liquid.
As the atmospheric pressure decreases, less vapor pressure is needed to cause the liquid to boil. Less vapor pressure means lower temperature.
The boiling point of cyclohexane at 620 mm Hg is less than 80.74˚C
TRY THAT OR THIS
271.78
