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Calculate the number of molecules in a deep breath of air whose volume is 2 35 L at body temperature 36 C and a presyre of 740 torr
Express the answer in molecules to three significant figures

5.426 x molecules are there in a deep breath of air whose volume is 2. 35 L at body temperature 36 C and a pressure of 740 torr.

Explanation:

Data given:

volume V = 2.35 L

Temperature T = 36 Degrees or 273.15 + 36 = 309.15 K

pressure P = 740 torr OR 0.973 Atm

R = 0.08205 L atm / mole K

n (number of molecules of gas)= ?

The formula used will be

PV = nRT

Putting the value of given variables in above equation:

n =

 =

 = 0.0901 moles

According to Avagadro' s law that gases at equal volume, temperature and pressure contains same molecules.

number of molecules:

number of moles x avagadro number

0.0901 x 6.02 x

= 0.54 x

= 5.426 x molecules.

a. energy is absorbed in the reaction.

if in a given reaction the energy of products is greater than the energy of reactants it means that reaction is endothermic and during the reaction, the energy is absorbed by reactants. in an endothermic reaction, the products have more stored chemical energy than the reactants. and in this reaction the reactants are more stable than products before the compounds with less energy are always more stable.