Which best describes a compound such as magnesium oxide? an impure substance that is made up of two elements a mixture of two uncommon substances a mixture of two common elements a pure substance that is made up of different elements

A pure substance that is made up of different elements

Explanation:

D. a pure substance that is made up of different elements

Explanation:

Step-by-step explanation:

There are two types of pure substances: elements and compounds.

Elements are made up of only one type of atom. And compounds are pure substances, that are made up of more than one type of element. Like - magnesium oxide. It is a compound of a metal with a non-metal and is held together with ionic bonds.

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