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-use headphones
-do not take up extra seats/space using their luggage or bags
-be aware of their surrounding so they do not bump into people or step on their feet
Answer: Option (3) is the correct answer.
Explanation:
A reaction due to which there occurs change in chemical composition of reactants is known as a chemical reaction.
For example, evolution of heat when two substances combine together shows a chemical reaction has taken place between the substances.
Whereas a reaction which does not bring any changes in chemical composition of the reactants is known as a physical reaction.
For example, boiling point, melting point, mass, volume etc are all physical properties.
Thus, we can conclude that out of the given options a substance melts when sitting in the Sun, is not an indication of a chemical reaction.
Condensation releases water
Answer:
number of moles of =4.16mol
Explanation:
experiment data:
temperature= =273+22 k=295k
pressure=1.007 atm
volume is missing so assuming volume-=100L
using ideal law relationship
ideal gas means gas which occupies negligible space and there is no interaction between the molecules of gases.
PV=nRT
put all the experimental data, we get
n=4.15 mol
number of moles of =4.16mol