Practice free Chemistry NEET multiple-choice questions online with instant answers and detailed explanations. No login required.
An example of a disproportionation reaction provided in the text is:
For example, manganese (VI) becomes unstable relative to manganese(VII) and manganese (IV) in acidic solution. $3Mn^{VI}O_4^{2–} + 4H^+ \rightarrow 2Mn^{VII}O_4^{–} + Mn^{IV}O_2 + 2H_2O$. (NCERT, Chapter: The d - and f - Block Elements, Page 105)
As the oxidation number of a metal in its oxides increases, the ionic character of the oxide:
As the oxidation number of a metal increases, ionic character decreases. In the case of Mn, $Mn_2O_7$ is a covalent green oil. Even $CrO_3$ and $V_2O_5$ have low melting points. In these higher oxides, the acidic character is predominant. (NCERT, Chapter: The d - and f - Block Elements, Page 105)
Which of the following statements about the acidity of metal oxides is correct?
$V_2O_5$ is, however, amphoteric though mainly acidic and it gives $VO_4^{3–}$ as well as $VO_2^+$ salts. In vanadium there is gradual change from the basic $V_2O_3$ to less basic $V_2O_4$ and to amphoteric $V_2O_5$. (NCERT, Chapter: The d - and f - Block Elements, Page 105)
Which of the following transition elements does NOT exhibit variable oxidation states?
Scandium (Z = 21) does not exhibit variable oxidation states. (NCERT, Chapter: The d - and f - Block Elements, Page 99)
In the 3d series, the ability of fluorine to stabilize the highest oxidation state is due to:
The ability of fluorine to stabilise the highest oxidation state is due to either higher lattice energy as in the case of $CoF_3$, or higher bond enthalpy terms for the higher covalent compounds, e.g., $VF_5$ and $CrF_6$. (NCERT, Chapter: The d - and f - Block Elements, Page 99)
Which of the following describes the function of a secondary battery?
According to the NCERT text, 'A secondary cell after use can be recharged by passing current through it in the opposite direction so that it can be used again.' This allows it to be used multiple times.
What is the approximate cell potential of a mercury cell and how does it behave during its lifespan?
The NCERT text states: 'The cell potential is approximately 1.35 V and remains constant during its life as the overall reaction does not involve any ion in solution whose concentration can change during its lifetime.'
Which of the following statements is true regarding fuel cells?
The NCERT text defines fuel cells as 'Galvanic cells that are designed to convert the energy of combustion of fuels like hydrogen, methane, methanol, etc. directly into electrical energy are called fuel cells.'
In a lead storage battery, what acts as the anode and cathode during discharge?
The NCERT text states: 'It consists of a lead anode and a grid of lead packed with lead dioxide (PbO$_{2}$) as cathode.'
What is the electrolyte used in a lead storage battery?
The NCERT text mentions: 'A 38% solution of sulphuric acid is used as an electrolyte' in the lead storage battery.
Ready to ace NEET?
Free access · No credit card required
Yes. You can attempt every Chemistry question on this page for free without logging in, and check the correct answer with a detailed explanation instantly.
No account is required to attempt questions and view answers. A free account adds bookmarks, personal notes, and progress tracking.
The bank mixes NEET previous year questions (PYQs) with practice questions, each tagged with its exam appearances where applicable.