Balance the following half-reaction: (acidic) no−3(aq) → no2(aq) express your answer as a half-reaction. identify all of the phases in your answer.

2H⁺  + NO₃⁻  + 1e⁻ →  NO₂  + H₂O

Explanation:

NO₃⁻  →  NO₂

In left side, Nitrogen acts with +5 by oxidation number

In right side, the oxidation number is +4

This is a reduction reaction, because the oxidation number has decreased. So the N has gained electrons.

NO₃⁻  + 1e⁻ →  NO₂

In acidic medium, we have to add water, where there are less oxygens to ballance the amount. We have 2 O in left side, and 3 O in right side, so we have to add 1 H₂O on left side.

NO₃⁻  + 1e⁻ →  NO₂  + H₂O

Now that oxygens are ballanced, we have to ballance the hydrogens by adding protons in the opposite side

2H⁺  + NO₃⁻  + 1e⁻ →  NO₂  + H₂O

answer is: naturally occurring solid, inorganic compound or element is mineral.

minerals usually have crystalline form, that means than crystal constituents (atoms, molecules or ions) are arranged in a highly ordered microscopic structure, forming a crystal lattice that extends in all directions.

for example magnetite is a mineral of iron oxide (fe₂o₃).

calcite is a carbonate mineral and the most stable polymorph of calcium carbonate (caco₃).

dolomite is an   carbonate mineral composed of calcium magnesium carbonate (camg(co₃)₂).