Ne(g) effuses at a rate that is times that of kr(g) under the same conditions.

                  Ne effuses at a rate that is 2.05 times that of Kr under the same conditions

                  According to Graham's Law of Effusion, "the rate of effusion of a gas is inversely proportional to the square root of its density or molar mass".

Mathematically,

                                      Rₐ / Rₓ  =      ----- (1)

Where;

           Rₐ  =  Rate of effusion of Ne

           Rₓ  =  Rate of effusion of Kr

           Mₐ  =  Molar Mass of Ne  =  20.18 g.mol⁻¹

           Mₓ  =  Molar Mass of Kr  =  84.80 g.mol⁻¹

Putting values in equation 1,

                                      Rₐ / Rₓ  =  

                                      Rₐ / Rₓ  =  

                                      Rₐ / Rₓ  =  2.05

         Hence, Ne effuses 2.05 times faster than Kr.

when the volume of gas is   changed from   717.73 ml   to 852 ml   the temperature will   change   from 315   c to 452   c

    calculation

this is calculated using the charles law formula

that is,   v1/t1 = v2/t2

          v1=?

        t1 = 315 c   into   kelvin = 315 +273 = 588 k

        v2 = 852   ml

        t2 = 425c + 273 =698 k

make v1   the subject of the formula ( by   multiplying both side by t1)

  v1=( v2 xt1) / t2

v1= (852 ml   x 588 k)/ 698 k= 717.73 ml

o conteúdo de calor de um sistema é igual à entalpia apenas para um sistema que é constante