Chemistry - Study Mode
[#861] Methanoic and ethanoic acids can be distinguished by the action of
Correct Answer
(C) Tollen's reagent
Explanation
Solution: Tollen's reagent (ammoniacal silver nitrate solution) can be used to distinguish between methanoic acid and ethanoic acid.
[#862] Which of the following alkali metals has highest specific heat?
Correct Answer
(D) Lithium
Explanation
Solution: Lithium has the highest specific heat capacity of any solid element. Because of its specific heat capacity, the highest of all solids, lithium metal is often used in coolants for heat transfer applications. It belongs to the alkali metal group of chemical elements. Under standard conditions it is the lightest metal and the least dense solid element. Like all alkali metals, lithium is highly reactive and flammable. For this reason, it is typically stored in mineral oil.
[#863] The first organic compound synthesised in the laboratory was
Correct Answer
(A) Urea
Explanation
Solution: In 1828, german chemist Wohler prepared urea in a laboratory from ammonium cyanate . This was the first organic compound synthesized artificially from inorganic materials.
[#864] Among the following, carbonate ore of Zinc is
Correct Answer
(B) Calamine
Explanation
Solution: Among the following, carbonate ore of Zinc is Calamine.
[#865] The metal used for making aircrafts and rockets is
Correct Answer
(B) Aluminium
Explanation
Solution: Aluminium is the metal commonly used for making aircraft and rockets due to its advantageous properties. Aluminium is lightweight, which is crucial for aircraft and rocket construction to reduce fuel consumption and increase payload capacity. Additionally, aluminium has good corrosion resistance, which is important for structures exposed to harsh environmental conditions, such as those encountered during flight. Lead, nickel, and copper are not typically used for making aircraft and rockets due to factors such as weight, strength, and corrosion resistance. Option A: Lead is not suitable for aircraft and rocket construction due to its high density and poor strength-to-weight ratio. Option B: Aluminium is the correct choice, as explained above. Option C: Nickel is not commonly used for aircraft and rocket construction. While nickel may be used in certain aerospace applications, it is not the primary metal used for aircraft and rockets. Option D: Copper is also not typically used for making aircraft and rockets due to its high density and poor strength-to-weight ratio compared to aluminium.