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In chemistry 22.4litres of gas weighs 70g at S.T.P.Calculate weight of gas if occupies...

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cherrybhatnagar | Student, Undergraduate | eNoter

Posted June 30, 2009 at 10:44 AM via web

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In chemistry 22.4litres of gas weighs 70g at S.T.P.Calculate weight of gas if occupies volume of 20litres at 27degree celsius and 700mmHg of pressure

it's a numerical of chemistry based on boyle's law and charles law.

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neela | High School Teacher | Valedictorian

Posted June 30, 2009 at 1:38 PM (Answer #1)

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By gas law:

PV= nRT, where P is pressure of the gas at the temperature T and R is a gas constant and n is the substance of gas in moles.

Put values in the equation For STP and The given temprature and pressure situations.

760d)(22.4)=(70/200.59)R(273.15)                (1)

(700d)(20)=(x/200.59)R(273.15+27)               (2)

(1)/(2) eleminates R and reduces To:

760*22.4/(700*20) = (70/x)(273.15)/290.15

x=70*273.15*700*20/(290.15*760*22.4)

= 54.17 g

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revolution | College Teacher | Valedictorian

Posted February 23, 2010 at 11:19 PM (Answer #2)

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It is 54 grams, correct to the nearest number. It is based on the formula, known as the gas law, which is PV= nRT. The figures can be directly put inside and solved. The rest is up to you to decide on how do you want to proceed.

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