`1.0g` of magnesium ribbon was placed in a crucible and heated with the lid on, until the magnesium began to burn brilliantly. At the end of experiment, there was `1.45 g` of white powder.
Show that this result does not agree with the equation:
`2Mg_((s))+O_(2(g))rarr2MgO_((s))`
Give an explanation for your answer.

Explanation

`underset(=48 g)underset(24xx2 g)(2Mg_((s)))+O_(2(g))rarrunderset(=80 g)underset((24+16)xx2 g)(2 MgO_((s)))`
`48 g` of magnesium ribbon gives `80 g` of `MgO`
`:. 1.0 g` of magnesium ribbon gives `=(80)/(48)xx1.0 g` of `MgO=1.66 g` of `MgO`
the actual amount of white ash produced `=1.45 g` The possible reasons are:
a. Some of `MgO` escaped as smoke.
b. magnesium did not react completely.
c. magnesium might have reacted with `N_(2)` (air) to form magnesium nitride.