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:
Throughout the overview section following portion, the description and according to particular circumstance is defined.
Explanation:
As per the question,
⇒ 
- A weak basis seems to be NH3. It serves as a base since the aqueous solution or phase is protonated. But NH3 +, just becoming a weak base, is therefore deprotonated into form NH3, and therefore also 90% of ammonia becomes found throughout NH3 state in aqueous solution.
⇒ 
However, it is also available in NH3 form throughout the aqueous solution much of the moment.
The balanced chemical reaction:
C3H8 + 5O2 = 3CO2 + 4H2O
We are given the amount of the carbon dioxide to be produced. This will be the starting point of our calculations.
<span>43.62 L CO2 ( 1 mol CO2 / 22.4 L CO2 ) (5 mol O2 / 3 mol CO2 ) (
22.4 L O2 / 1 mol O2) = 72.7 L O2</span>
Metals are ductile,malleable,good conductors and shiny