PLEASE ANSWER, I WILL GIVE BRAINLIEST AND THANKS! 48g of magnesium and 32g of oxygen react to form 80g of magnesium oxide. 2Mg + O2 --> 2MgO What mass of oxygen is needed to make 20g of MgO?

Mass of oxygen needed  = 8 g

Explanation:

Given data:

Mass of oxygen needed = ?

Mass of MgO formed  = 20 g

Solution:

Chemical equation:

2Mg + O₂     →    2MgO

Number of moles of MgO:

Number of moles = mass/molar mass

Number of moles = 20 g/ 40 g/mol

Number of moles = 0.5 mol

Now we will compare the moles of MgO and O₂:

                        MgO         :            O₂

                           2            :            1

                          0.5          :        1/2×0.5 = 0.25 mol

Mass of oxygen needed:

Mass = number of moles × molar mass

Mass = 0.25 mol × 32 g/mol

Mass = 8 g

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i think? ?

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