Answer:
Only Mn⁺² is present.
Explanation:
- When an aqueous solution of NaCl is added, the Cl⁻ species is introduced. In the presence of Cl⁻, Hg₂²⁺ would precipitate as Hg₂Cl₂.
- When an aqueous solution of Na₂SO₄ is added, the SO₄⁻² species is introduced. In the presence of SO₄⁻², Ba⁺² would precipitate as BaSO₄.
No precipitate formed when either of these solutions were added, thus <u>the sample does not contain Hg₂⁺² nor Ba⁺²</u>.
- Under basic conditions Mn⁺² would precipitate as Mn(OH)₂. A precipitate formed once the solution was made basic, so <u>the sample contains Mn⁺²</u>.
Kl alabayel ma almtran ashaw yabn alam
Answer:
C. Hydrogen Ions.
Explanation:
The pH level of soils is measured based upon the acidity or basicity level in the soil. The pH scale usually measures between 0-14. 7 is the neutral pH level of soil and a pH level below 7 is considered acidic and above 7 is alkaline.
So, soil with a high amount of hydrogen ions (H+) will be considered acidic. As the amount of hydrogen ions increases in the soil, the pH level of the soil decreases, making it acidic.
Therefore, option C is correct.