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:
A neutron transforms into a proton and an electron.
Explanation:
i took the test got an 100%
Answer:
False
Explanation:
The primary structure of a protein refer to the amino acid sequence. The secondary structure of a protein refer to the alpha helices, beta sheets and turns, while the tertiary structure refer to folding of the sheets due to hydrogen bonding or other bonding interaction between them.
Answer:
Scandium(III) fluoride, ScF3, is an ionic compound. It is slightly soluble in water but dissolves in the presence of excess fluoride to form the ScF63− anion.
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