When elements transfer electrons from a cation and an anion it called ionic bond.
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.
The reduction of alkyne to an alkene in the first step allows the best reagent to be chosen for each subsequent step.
Describe reagents.
A reagent is merely an essential component of a chemical reaction, it should be mentioned. It is an ingredient that speeds up the reaction.
With H2 and Lindlar's catalyst, an alkyne is reduced to alkene as the initial step in this process. Alkene will then be brominated to produce allyl bromide as the next step.
In this instance, the required allyl alcohol will be produced via the reaction of allyl bromide with NaOH.
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