Answer:
3Fe(s)+2O2(g)---->Fe3O4
this way you will have 3irons on both sides and 4 oxygens.
I hope this helps
Additional information
Relative atomic mass(Ar) : A=7, G=16
The empirical formula : A₂G
<h3>Further explanation</h3>
Given
3.5g of element A
4.0g of element G
Required
the empirical formula for this compound
Solution
The empirical formula is the smallest comparison of atoms of compound forming elements.
The empirical formula also shows the simplest mole ratio of the constituent elements of the compound
mol of element A :

mol of element G :

mol ratio A : G = 0.5 : 0.25 = 2 : 1
Salutations!
<span>In a laboratory experiment, John uses a mesh to separate soil particles from water. Which technique of separation is he using?
The technique that John is using is the filtration technique. Filtration is a technique to separate the solid which is insoluble from the liquid. For instance: Sand and water, sand is insoluble, thus it stays in the filter paper, while the water proceeds through the filter paper.
Hope I helped :D</span>
Isotopes of elements where the nucleas is unstable generally release nuclear radiation. So unstable atoms
The vapor pressure (in torr) of a 35°C solution : 52 torr
<h3>Further explanation</h3>
Given
x propanol = 0.75
P°ethanol=100 torr
P°propanol=36 torr
Required
the vapor pressure
Solution
Raoult's Law
P solution = xA.P°A +xB.P°B
x ethanol = 1- 0.75 = 0.25
Input the value :
P solution = 0.25 x 100 + 0.75 x 36
P solution = 25 + 27
P solution = 52 torr