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The pair of compounds that can exist together is:
Given below are two statements: Assertion (A): Ionisation enthalpies of early actinoids are lower than early lanthanoids. Reason (R): Electrons entering $5f$ orbitals in actinoids experience greater shielding from the nuclear charge. In the light of the above statements, choose the most appropriate answer from the options given below:
4NH₃ + 5O₂ → 6H₂O + 4NO When 1 mole of ammonia (NH₃) reacts with 1 mole of oxygen (O₂), which of the following outcomes occurs regarding the consumption of the reactants?
An incorrect statement among the following is :
It is because of the inability of $ns^2$ electrons of the valence shell to participate in bonding that:
The stability of +1 oxidation state among Al, Ga, In and Tl increases in the sequence?
Which one of the following does not correctly represent the correct order of the property indicated against it?
Name the type of the structure of silicate in which one oxygen atom of $[\text{SiO}_4]^{4-}$ is shared?
If enthalpies of formation of $C_{2}H_{4}(g)$, $CO_{2}(g)$ and $H_{2}O(l)$ at $25^{\circ}C$ and 1 atm pressure be 52, –394 and –286 kJ mol⁻¹ respectively, the enthalpy of combustion of $C_{2}H_{4}(g)$ will be [CBSE PMT 1995; AIIMS 1998; Pb. PMT 1999]:
Select the correct statements from the following: A. Atoms of all elements are composed of two fundamental particles. B. The mass of the electron is $9.10939 \times 10^{-31}$ kg. C. All the isotopes of a given element show the same chemical properties. D. Protons and electrons are collectively known as nucleons. E. Dalton's atomic theory regarded the atom as an ultimate particle of matter. Choose the correct answer from the options given below:
Which of the following oxidation states are the most characteristics for lead and tin respectively?
Percentage of C, H & N in a compound is given as follows: C=40%; H=13.33%; N=46.67% The empirical formula of the compound will be:
Which of the following options incorrectly describes the possible range of values for the mole fraction ($x$) of a component in a mixture?
The number of $d$-electrons in $\text{Fe}^{2+}$ (atomic number $Z = 26$) is different from the number of:
The chain length of silicones can be controlled by adding:
Identify the correct relationship of stability from the options provided:
Match List-I (Molecules) with List-II (Shapes): List-I: (a) $PCl_5$ (b) $SF_6$ (c) $BrF_5$ (d) $BF_3$ List-II: (i) Square pyramidal (ii) Trigonal planar (iii) Octahedral (iv) Trigonal bipyramidal Choose the correct answer from the options given below:
Which of the following ions have the same 'spin-only' magnetic moment? A. $Ti^{3+}$ B. $Cr^{2+}$ C. $Mn^{2+}$ D. $Fe^{2+}$ E. $Sc^{3+}$ Choose the most appropriate answer from the options given below:
Match the allotropes of carbon given in List I with the respective characteristics given in List II. **List-I** (A) Coke (B) Diamond (C) Fullerene (D) Graphite **List-II** I. Carbon atoms are $sp^3$ hybridised. II. Used as a dry lubricant III. Used as a reducing agent IV. Cage like molecules Choose the correct answer from the options given below:
The correct order of atomic radii of the group 13 elements is-