Description : Sp3d2 hybridization of central atom of a molecule would lead to............ geometry. a) square planar b) Tetrahedral c) Trigonal bipyramidal d) Octahedral
Last Answer : d) Octahedral
Description : During the formation of bond..... a) Energy decreases b) Energy increases c) Energy of system does not change d) Electron-electron repulsion becomes more than Nucleus-electron attraction
Last Answer : a) Energy decreases
Description : For stable structures, one of the important properties of flexibility and stiffness matrices is that the elements on the main diagonal (i) Of a stiffness matrix must be positive (ii) Of a stiffness matrix must be negative (iii) Of ... ) (B) (ii) and (iii) (C) (i) and (iv) (D) (ii) and (iv)
Last Answer : (A) (i) and (iii)
Description : Why does a H+ ion attacking a carbon-carbon double bond add to the carbon with the least number of substituents? (a) the reaction is resonance stabilized. (b) the hybrid geometry favors this ... tends to attack stable centers of negative charge. (d) a more stable carbonium ion is generated.
Last Answer : a more stable carbonium ion is generated.
Description : When radiation breaks an electron pair bond in a molecule and each fragment of the molecule gets one of the bond electrons, the molecular fragments that are formed are called: w) ions x) free radicals y) stable molecules z) gases
Last Answer : ANSWER: X -- FREE RADICALS
Description : Choose the wrong statement (A) The center of buoyancy is located at the center of gravity of the displaced liquid (B) For stability of a submerged body, the center of gravity of body must ... the submerged body must lie at neutral equilibrium for all positions (D) All floating bodies are stable
Last Answer : Answer: Option D
Description : The isoelectric point of a protein is (a) the pH at which the protein molecule has no charges on its surface. (b) the pH at which a protein in solution has an equal number of positive and negative charges. (c) the electric charge under isothermal conditions. (b) None of these
Last Answer : the pH at which a protein in solution has an equal number of positive and negative charges
Description : Electron-withdrawing groups are meta directors because : (a) the carbonium ion intermediate has a negative charge on the meta position. (b) the more stable resonance hybrid occurs with meta ... the electrophile. (d) the carbonium ion intermediate has a positive charge on the meta position
Last Answer : the more stable resonance hybrid occurs with meta attachment of the electrophile.
Description : Differentiate between positive and negative feedback on the basis of . (i) overall phase shift (ii) voltage gain (iii) stability (iv) applications
Last Answer : Compare positive feedback and negative feedback on the basis of: (i) Gain (ii) Bandwidth (iii) Phase shift (iv) Stability
Description : What is the name given to a polar molecule or negative ion that is clustered about a central positive ion?
Last Answer : ANSWER: LIGAND
Description : What happens when a chemical bond is formed? (1) energy is always absorbed (2) energy in always released (3) more energy is released than is absorbed (4) energy is neither released nor ... as potential energy. Upon the breaking of these bonds the energy is released thereby creating usable energy.
Last Answer : Silver nitrate solution is kept in brown bottles in laboratory because - (1) it reacts with ordinary white bottles (2) brown bottles stops the passage of light through it (3) brown bottles do not react with it (4) brown bottles react with it
Description : The compound methylamine, H3C–NH2, contains a C–N bond. In this bond, which of the following best describes the charge on the nitrogen atom? (a) slightly positive (b) uncharged (c) slightly negative (d) –1
Last Answer : slightly negative
Description : Which of the following is incorrect? (a) Resonance stabilization is the extra stability a compound gains from having delocalized electrons. (b) Delocalized electrons destabilize a compound. (c) The greater ... stable resonance contributors, the greater is the resonance stabilization. (d) (a) and (c)
Last Answer : Delocalized electrons destabilize a compound
Description : With increasing bond order, stability of a bond (a) Decreases (b) Increases (c) Remains unchanged (d) None of these
Last Answer : Ans:(b)
Description : Which statement about the structure of benzene is not true? (a) The two Kekule structures of benzene are in equilibrium. (b) The carbon-carbon bond lengths in benzene are greater than the carbon- ... (d) The stability of benzene ring is much greater than the stability of 1,3,5- cycloheptatriene
Last Answer : The two Kekule structures of benzene are in equilibrium
Description : Define bond order and give the relationship between bond order and bond length
Last Answer : Ans Bond order (b.o.) is defined as one half the difference between the number of electrons present in the bonding and the antibonding orbitals i.e., Bond order (b.o.) = ½ (Nb–Na) Bond order is inversely proportional to bond length
Description : What is a type of bond in which positive and negative charged ions attract each other in an ionic bond?
Last Answer : That is called an ionic bond or coulombic attraction.
Description : When a positive ion is attracted to a negative ion what’s the chemical bond called?
Last Answer : Ionic Bond
Description : When a positive ion is attracted to a negative ion what’s the chemical bond?
Description : The effective atomic number of `Co(CO)_(4)` is 35 and hence is less stable. It attains stability by
Last Answer : The effective atomic number of `Co(CO)_(4)` is 35 and hence is less stable. It attains stability by ... Co B. reduction of Co C. dimerization D. none
Description : Are Mizuno stability shoes stable?
Last Answer : This type of shoe is specifically designed to help improve stability while running, thanks to the under-arch support it provides. Check with your doctor if you have current injuries, but it might well help!
Description : A body floats in stable equilibrium (A) When its meatcentric height is zero (B) When the metacentre is above e.g. (C) When its e.g. is below its center of buoyancy (D) Metacentre has nothing to do with position of e.g. for determining stability
Last Answer : Answer: Option B
Description : The Metacentric heights of two floating bodies A and B are 1 m and 1.5 m respectively. Select the correct statement. (A) The bodies A and B have equal stability (B) The body A is more stable than body B (C) The body B is more stable than body A (D) The bodies A and B are unstable
Last Answer : Answer: Option C
Description : ________ is a quantitative measure of how fair the transients die cut in the system. (a) Absolutely stable (b) Conditionally stable (c) Unstable (d) Relative stability
Last Answer : (d) Relative stability
Description : Define stability. Sketch the root locations in the s-plane for stable and unstable system.
Last Answer : Stability: The system is said to be stable if it produces bounded output for a bounded input. It is used to define usefulness of the system. The stability implies that the system performance should not ... absence of the input, output may not return to zero it shows certain output without input.
Description : A conditionally stable system exhibits poor stability at
Last Answer : A conditionally stable system exhibits poor stability at reduced values of open loop gain.
Description : Which of the following statements about benzene is correct? (a) All of the carbon atoms are sp3 hybridized. (b) It has no delocalized electrons. (c) The carbon-carbon bond length is longer than that of ethane. (d) It is a planar molecule.
Last Answer : It is a planar molecule.
Description : What is the bond order of a N2+ molecule?
Last Answer : answer is 2
Description : Ionisation energy of nitrogen is greater than that of oxygen because nitrogen has – (1) high bond dissociation energy (2) smaller atomic radius (3) stable half filled 2p sub level (4) high nuclear charge
Last Answer : (3) stable half filled 2p sub level Explanation: Ionization energy is a measure of the ease in which atoms lose electrons and become positive ions.
Description : Ionisation energy of nitrogen is greater than that of oxygen because nitrogen has (1) high bond dissociation energy (2) smaller atomic radius (3) stable half filled 2p sub level (4) high nuclear charge
Last Answer : stable half filled 2p sub level
Description : Describe the positive and negative aspects of relationship between caste and politics. -SST 10th
Last Answer : Advantages: (i) It gives disadvantaged groups the opportunity to demand a share in power and decisionmaking. (ii) Many political parties take up the issue of ending caste discrimination. (iii) ... as poverty, corruption etc. (ii) Caste based politics leads to tensions, conflicts and violence.
Description : The relationship between the value of money and the price level in an economy is - (1) Direct (2) Inverse (3) Proportional (4) Stable
Last Answer : (2) Inverse Explanation: The basic causal relationship between the price level and the value of money is that as the price level goes up, the value of money goes down. The "value of money" refers to ... price level" refers to the average of all of the prices of goods and services in a given economy.
Description : The relationship between the value of money and the price level in an economy is (1) Direct (2) Inverse (3) Proportional (4) Stable
Last Answer : Inverse
Description : Asseration: The thermal stability of hydrides of oxygen family decrease with molecular weight. Reason: The decomposition of `M-H` bond requires lesser
Last Answer : Asseration: The thermal stability of hydrides of oxygen family decrease with molecular weight. Reason: The decomposition ... in `O-H` than `S-H`.
Description : (A) : Thermal stability of the hydrides of VIA group elements decreases from `H_(2)O` to `H_(2)Po` (R) : The heats of dissociation of M - H bond of hy
Last Answer : (A) : Thermal stability of the hydrides of VIA group elements decreases from `H_(2)O` to `H_(2)Po` (R) : ... is false D. (A) is false but (R) is true
Description : In an oxygen molecule, two atoms are united by - (1) one bond (2) two bonds (3) three bonds (4) four bonds
Last Answer : (2) two bonds Explanation: Two oxygen atoms can both achieve stable structures by sharing two pairs of electrons as in the diagram. Two electrons of each of the atom in the oxygen molecule ... is shown conventionally by two lines joining the atoms. Each line represents one pair of shared electrons.
Description : How many hydrogen-bonded water molecule(s) are present in CuSO4.5H2O ? Draw its structure to show formation of hydrogen bond.
Last Answer : Ans- one molecule of water is bonded by hydrogen bond and is deeply embedded in the lattice, While four molecules are bonded with coordinate bond. [ Cu(H2O)4] SO4.H2O
Description : Is the bond energy of all the four C-H bonds in CH4 molecule equal? If not then why ? How is C-H bond energy then reported?
Last Answer : Ans. No because after breaking of C-H bonds one by one, the electronic environments change. The reported value is the average of of the bond dissociation energies of the four C-H bonds.
Description : Explain the formation of H2 molecule on the basis of valence bond theory.
Last Answer : Ans. When two H atoms come closer the following forces operate between them: a. Attractive : i.nucleus of atom and its electron ii.nucleus of one atom and electron of other. b.repulsive ... and the system acquires minimum energy .At this stage two hydrogen atoms are said to be bonded together.
Description : Which of the following statements are false about benzene? (a) It is a planar molecule with bond angles 120°. (b) It is immiscible with water forming the lower layer. (c) It can be ... Ni catalyst. (d) It reacts with ethyl chloride in the presence of aluminium chloride to form ethylbenzene.
Last Answer : It is immiscible with water forming the lower layer
Description : Triethylamine [(CH3CH2)3N] is a molecule in which the nitrogen atom is __________ hybridized and the CNC bond angle is __________. (a) sp2; >109.5° (b) sp2; 109.5° (d) sp3;
Last Answer : sp3;
Description : Explain why the water molecule has a bent shape and a bond angle less than 109.5° The electron repulsion between the two lone pairs of electrons on the oxygen of water causes the O–H bonds to squeeze close together
Last Answer : The electron repulsion between the two lone pairs of electrons on the oxygen of water causes the O–H bonds to squeeze close together
Description : What is the name given to the bond that links an amino group of one molecule of an amino acid to a carboxyl group of another amino acid?
Last Answer : ANSWER: PEPTIDE LINK or AMIDE LINK or PEPTIDE BOND
Description : In an oxygen molecule, two atoms are united by (1) one bond (2) two bonds (3) three bonds (4) four bonds
Last Answer : two bonds
Description : The total energy of revolving electron in an atom – (1) cannot be negative (2) can have any value above zero (3) can never be positive (4) will always be positive
Last Answer : (3) can never be positive Explanation: The total energy of a revolving electron in any orbit is the sum of its kinetic and potential energies. Energy of an electron at infinite distance from the ... and the energy of electron decreases and thus becomes negative. Thus, it can never be positive.
Description : The total energy of revolving electron in an atom (1) cannot be negative (2) can have any value above zero (3) can never be positive (4) will always be positive
Last Answer : can never be positive
Description : A yellow metallic powder is burnt in a stream of fluorine to obtain a colourless gas X which is thermally stable and chemically inert. Its molecule ha
Last Answer : A yellow metallic powder is burnt in a stream of fluorine to obtain a colourless gas X which is thermally stable ... and NaC1` D. `SF_(4) and SF_(6)`
Description : Why are parallel beta sheets less stable than anti-parallel beta sheets in a folded protein molecule?
Last Answer : Need answer
Description : Which one of the following statements is WRONG? (A) A singlet or triplet state may result when one of the electrons from the HOMO is excited to higher energy levels (B) In an ... the electron from the singlet excited state returns to ground state, the molecule always shows fluorescence phenomenon
Last Answer : (C) Triplet excited state is more stable than the singlet excited state