37. Is D
38. Is C
39. Is A
40. Is A
41. Is D I think!
I'm 100% positive about 37-40 but I'm 50% sure on question number 41.
I hope this helped!
Atomic mass is the quantity of protons that have in a atom. Which atom have different numbers of protons, being able to be identified by them.
Answer:
C. Gain in electron(s) resulting in a decrease of oxidation number.
Explanation:
Redox reactions are reactions involving transfer of of electron between two species (reduction specie) and (oxidation species) and change resulting in change in oxidation number.
Reduction in terms of redox reaction is the specie that accepts electron(s) and gets "reduced" since its oxidation state has been reduced.
For example
Cl + e- → Cl⁻
The above reaction is an example of reduction reaction taking place in a redox reaction. We can see that Chlorine oxidation state was changed from (0) to (-1) state.
I think it's Sodium Sulfide, because Na2S contains one Sodium and two Sulfur. Plus Sulfide<span> is used to describe any of three types of chemical compounds that contain sulfur.</span>