Answer:
I think the answer is A - they used X-ray analysis.
Explanation:
Answer:
c.- How much of the reactants are needed and how much product will made.
Explanation:
The moles is the matter unit used in chemistry to simplify some calculations, instead of using grams. Also the moles are very useful because the chemical reaction can be balanced.
When a Chemical reaction is balanced, then it can be easily to calculate how many moles are necessary to add in a process to obtain a quantity of grams of a product.
Losing electrons and forming positive ions
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>