First find the oxidation states of the various atoms:
<span>in Cr2O2 2- Cr @ +1; In NH3 N @ +3; in CrO3 Cr @ +3, N2 N @ 0 </span>
<span>Note that N gained electrons, ie, was reduced; Cr was oxidized </span>
<span>Now there is a problem, because B has NH4+ which the problem did not, and is not balanced, showing e- in/out </span>
<span>B.NH4+ → N2 </span>
<span>Which of the following is an oxidation half-reaction? </span>
<span>A.Sn 2+ →Sn 4+ + 2e- </span>
<span>Sn lost electrons so it got oxidized</span>
The crust of the Earth is thickest beneath the continents.
Number of moles:
1 mole ---------- 6.02x10²³ molecules
? moles --------- 9.45x10²⁴ molecules
1 x ( 9.45x10²⁴) / 6.02x10²³ =
9.45x10²⁴ / 6.02x10²³ => 15.69 moles of CH3OH
Therefore:
Molar mass CH3OH = 32.04 g/mol
1 mole ------------ 32.04 g
15.69 moles ----- mass methanol
Mass methanol = 15.69 x 32.04 / 1 => 502.7076 g