Answer:
OPTION (A) : Testing a rock sample for gold content
Explanation:
For testing a rock sample of gold content you will need a Chemist. To test the material, the sample is rubbed on black stone which will leave a mark on the stone. This mark is tested by applying aqua fortis i.e nitric acid on the mark. If the mark gets dissolve then the material is not gold. If the mark sustain the it is further tested by applying aqua regia i.e nitric acid and hydrochloric acid which will prove the sample is of gold if it gets dissolve on using hydrochloric acid. The purity of the sample can be checked by differing the concentration of the aqua regia and comparing it with the gold material of the known purity.
Answer:
Explanation:
Hello,
In this case, we could considering this as a redox titration:
Thus, the balance turns out (by adding both hydrogen ions and water):
Thus, by stoichiometry, the grams of Fe+2 ions result:
Finally, the mass percent is:
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Answer:C. The value of n for H+(H2O)n can be calculated for almost all solutions.
Explanation:
An hydrate can be described as a substance that contains water or with an hydrogen bonded water molecule group.
The hydrate group doesn't necessarily have a fixed formula.
I think that it is qualitative data
The question is asking us to determine what gives the Amethyst its purplish color. Amethyst colors range from light to dark purple. The most highly regarded are the transparent deep purple colors. Amethyst ( chemical formula: Si O2 ) is the purple variety of the mineral Quartz.The pure Quartz is often colorless. Amethyst gets its purplish color because of the presence of Iron ( Fe ) and other impurities in the gem. Answer: C. Iron.<span /><span />
