Asample of an unknown compound contains 82.63% c, and 17.37% h. determine the empirical formula.

The actual amount of substance doesn’t matter for this problem, so assume an easy mass of compound using the percentages: 82.63 g C and 17.37 g H. There is also no need to worry about significant figures in an empirical formula problem.

Find the number of moles of each element:

Find the ratio of the elements, and simplify until there are whole numbers that you can put into the empirical formula.

There are 5 mol H for every 2 mol C, so the empirical formula should be .

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

i just calculated it all out, and not including weekends, and all the different days off. as of this school year (2018-2019) students are spending 2198 hours in school this year