Fehling’s solution ‘A’ is
- aqueous copper sulphate
- alkaline copper sulphate
- alkaline solution of sodium potassium tartrate (Rochelle’s salt)
- aqueous sodium citrate
The Correct Option is A
Solution and Explanation
Fehling's solution is used in chemical tests to differentiate between water-soluble aldehydes and ketone functional groups. It is typically composed of two separate solutions which are mixed in equal parts just before the test.
Fehling's solution ‘A’ specifically refers to an aqueous solution of copper(II) sulphate. It is one of the critical components that combine with solution ‘B’ to form Fehling's reagent.
| Component | Description |
|---|---|
| Fehling’s solution 'A' | Aqueous copper sulphate |
| Fehling’s solution 'B' | Alkaline solution containing sodium potassium tartrate (Rochelle's salt) |
When combined, these solutions create a complex that, upon heating with an aldehyde, leads to a red precipitate being formed due to the reduction of copper(II) ions to copper(I) oxide.
Top NEET Chemistry Questions
Which of the following statements are true?
A. Unlike Ga that has a very high melting point, Cs has a very low melting point.
B. On Pauling scale, the electronegativity values of N and C are not the same.
C. $Ar, K^{+}, Cl^{–}, Ca^{2+} and S^{2–}$ are all isoelectronic species.
D. The correct order of the first ionization enthalpies of Na, Mg, Al, and Si is Si $>$ Al $>$ Mg $>$ Na.
E. The atomic radius of Cs is greater than that of Li and Rb.
Choose the correct answer from the options given below:- NEET (UG) - 2025
- Chemistry
- Inorganic chemistry
- Given below are two statements:
Statement I: Like nitrogen that can form ammonia, arsenic can form arsine.
Statement II: Antimony cannot form antimony pentoxide.
In the light of the above statements, choose the most appropriate answer from the options given below:- NEET (UG) - 2025
- Chemistry
- Inorganic chemistry
For the reaction A(g) $\rightleftharpoons$ 2B(g), the backward reaction rate constant is higher than the forward reaction rate constant by a factor of 2500, at 1000 K.
[Given: R = 0.0831 atm $mol^{–1} K^{–1}$]
$K_p$ for the reaction at 1000 K is:- NEET (UG) - 2025
- Chemistry
- Law Of Chemical Equilibrium And Equilibrium Constant
Among the following, choose the ones with an equal number of atoms.
- 212 g of Na2CO3 (s) [molar mass = 106 g]
- 248 g of NaNO3 (s) [molar mass = 62 g]
- 240 g of NaOH (s) [molar mass = 40 g]
- 12 g of H2 (g) [molar mass = 2 g]
- 220 g of CO2 (g) [molar mass = 44 g]
Choose the correct answer from the options given below:
- NEET (UG) - 2025
- Chemistry
- Stoichiometry and Stoichiometric Calculations
Identify the suitable reagent for the following conversion: $Ph-C(=O)-OCH_3$ $\longrightarrow$ $Ph-CHO$
- NEET (UG) - 2025
- Chemistry
- Organic Chemistry
Top NEET Types of Solutions Questions
- The mixture which shows positive deviation from Raoult’s law i s :
- NEET (UG) - 2020
- Chemistry
- Types of Solutions
- The mixture that forms maximum boiling azeotrope is :
- NEET (UG) - 2019
- Chemistry
- Types of Solutions
- The boiling point of 0.2 mol kg$^{-1}$ solution of X in water is greater than equimolal solution of Y in water. Which one of the following statements is true in this case ?
- NEET (UG) - 2015
- Chemistry
- Types of Solutions
- The pair of compounds that can exist together is
- NEET (UG) - 2014
- Chemistry
- Types of Solutions
- The vapour pressure of a solvent decreased by 10 mm o f mercury when a non-volatile solute was added to the solvent. The mole fraction of the solute in the solution is 0.2. What should be the mole fraction of the solvent if the decrease in the vapour pressure is to be 20 mm o f mercury?
- NEET (UG) - 1998
- Chemistry
- Types of Solutions
Top NEET Questions
- With the help of the given pedigree, find out the probability for the birth of a child having no disease and being a carrier (has the disease mutation in one allele of the gene) in the F3 generation.
- NEET (UG) - 2025
- Genetics
- Which of the following enzyme(s) are NOT essential for gene cloning?
A. Restriction enzymes
B. DNA ligase
C. DNA mutase
D. DNA recombinase
E. DNA polymerase- NEET (UG) - 2025
- Molecular Biology
A constant voltage of 50 V is maintained between the points A and B of the circuit shown in the figure. The current through the branch CD of the circuit is :
- NEET (UG) - 2025
- Current electricity
- Frogs respire in water by skin and buccal cavity and on land by skin, buccal cavity and lungs.
- NEET (UG) - 2025
- Animal Physiology
Which of the following statements are true?
A. Unlike Ga that has a very high melting point, Cs has a very low melting point.
B. On Pauling scale, the electronegativity values of N and C are not the same.
C. $Ar, K^{+}, Cl^{–}, Ca^{2+} and S^{2–}$ are all isoelectronic species.
D. The correct order of the first ionization enthalpies of Na, Mg, Al, and Si is Si $>$ Al $>$ Mg $>$ Na.
E. The atomic radius of Cs is greater than that of Li and Rb.
Choose the correct answer from the options given below:- NEET (UG) - 2025
- Inorganic chemistry