Description : What is the highest oxidation state shown by Cr. (24) , Mn(25) ?
Last Answer : Ans: Cr. Shows (+6) and Mn Shows (+7) Oxidation state .
Description : Why do transition metals have higher I.E than s –block elements ?
Last Answer : Ans: It is due to smaller atomic size than s-block elements , effective nuclear charge is more , terefore I.E is high.
Description : Why are Ti+2 and other transition metals and their ions paramagnetic ?
Last Answer : Ans: These ions have unpaired electrons in d- subshell.
Description : Why is K2Cr2O7 generally preferred over Na2Cr2O7 in a volumetric analysis .Give reason .
Last Answer : Ans : It is because Na2Cr2O7 is hygroscopic in nature that is why it absorbs moisture from atmosphere , therefore its standard solution can not be prepared .
Description : Explain the following , giving reason . (a) Transition metal and many of their compounds show paramagnetic behavior (b) The enthalpy of atomisation of the transition metal is high . (c) The Transition metal generally form coloured compounds .
Last Answer : Ans(a) It is due to unpaired electrons . (b) It is due to strong metallic bond and additional Covalent bonds due to presence of unpaired electron in d- orbitals (c) It is due to presence of unpaired electrons ,they undergo d-d transition .
Description : Why are lanthanoid colored and paramagnetic L
Last Answer : Ans It is due to presence of unpaired electrons, they are paramagnetic and they absorb light From visible region and undergoes f-f transition and radiate complementary colour .
Description : Why are transition metal fluorides are ionic in nature where as chlorides and bromides are covalent in nature .
Last Answer : Ans - It is because of fluorine is most electronegative where as Cl and Br are less electro negative . Greater the difference in electro negativity more will be ionic character .
Description : Why is Cu+1 diamagnetic and Cu +2 paramagnetic ?
Last Answer : It is because Cu+ does not have unpaired electrons where as Cu+2 has unpaired electrons in d-sub cell .
Description : Why do Zr and Hf show similar properties ?
Last Answer : Ans It is due to similar ionic size which due to lanthanide contraction .
Description : Why are Cr+ , Ag+ & Sc+3 Colour less ?
Last Answer : Ans It is because they do not have unpaired electrons ,therefore can not under goes d-d transition .
Description : Why are transition metals and there compounds generally coloured ?
Last Answer : Ans It is due to present of unpaired electrons in transition metals and their ions , that is why they absorbed light from visible region and undergoes d-d transition and radiate complementary colour .
Description : Why does V2O5 acts as catalyst ?
Last Answer : Ans : It is because V shows variable O.S .
Description : What is an lanthanoid contraction ? What is its cause ? Give its consequences .
Last Answer : Ans The decrease in atomic and ionic size with increase in atomic no. in lanthanoid series is called lanthanoid contraction . The cause of lanthanoid contraction is poor shielding effect of d and f ... is close resemblance between elements of 4 d and 5 d transition series . due to similar ionic
Description : Why Ce+3 Can be easily Oxidised to Ce+4 ?
Last Answer : Ans : It is because Ce+4 has stable electronic configuration .
Description : Why do transition metals have high enthalpy of atomization ?
Last Answer : Ans : it is due to strong metallic bonds and additional covalent bonds
Description : Why are Zn , Cd , Hg are not regarded as transition metals ?
Last Answer : Ans: It is because neither they nor their ions have incompletely filled d- orbitals .
Description : What are d Block Elements ?
Last Answer : Ans: Those elements in which d-orbital are progressively filled up are known as d-orbital.
Description : Application of d- & f- block elements
Last Answer : Application of d- & f- block elements:- 1. Iron and steel used in construction,as catalyst in Haber's process 2. CrO2 is used in magnetic tapes 3. Ni is in hydrogenation 4. W ( ... in contact process 9. Titanium is in nuclear reactions. 10. PdCl2 is in Wacker's process.
Description : Newlands' table, the elements were placed with the halogens - (1) Mn and As (2) Fe and Se (3) Ce and La (4) Co and Ni
Last Answer : (4) Co and Ni Explanation: Newlands' Law of Octaves suffered from lot of limitations, In order to fit elements into his table, Newlands ad justed two elements in the same slot, but also put some unlike elements under the same note.
Description : The deficiencies of micronutrients, not only affect growth of plants but also vital functions such as photosynthetic and mitochondrial electron flow. Among the list given below, which group of three elements shall affect most, both ... , Mo (b) Ca, K, Na (c) Mn, Co, Ca (d) Cu, Mn, Fe
Last Answer : d) Cu, Mn, Fe
Description : The pair having the same magnetic moment is [at. No. `Cr = 24, Mn = 25, Fe = 26 " and " Co = 27]`
Last Answer : The pair having the same magnetic moment is [at. No. `Cr = 24, Mn = 25, Fe = 26 " and " Co = 27]` A. `[Cr( ... (H_(2)O)_(6)]^(2+) and [CoCl_(4)]^(2-)`
Description : A cofactor required for the activity of the enzyme ALA dehydratase is (A) Cu (B) Mn (C) Mg (D) Fe
Last Answer : Answer : A
Description : Soils with high pH are generally deficient in:? a Zn and Mn b B and Fe c Cu and Mo d Ca and Mg
Last Answer : a Zn and Mn
Description : Gray spots of oat are caused by deficiency of (a) Cu (b) Zn (c) Mn (d) Fe.
Last Answer : (c) Mn
Description : Which is essential for the growth of root tip? (a) Zn (b) Fe (c) Ca (d) Mn
Last Answer : (c) Ca
Description : Which of the following is present in Chlorophyll molecule ? (1) Mn (2) Mg (3) Fe (4) K
Last Answer : Mg
Description : Name the reducing agent in the following reaction: 3MnO2 + 4Al———— > 3Mn + 2Al2O3 State which is more reactive, Mn or A1 and why? -Chemistry
Last Answer : ‘Al’ is reducing agent. ‘AT is more reactive than Mn v ‘Al’ displaces Mn from its oxide.
Description : Which one is an essential mineral, not constituent of any enzyme but stimulates the activity of many enzymes? (a) Zn (b) Mn (c) K (d) Mg
Last Answer : (c) K
Description : Consider a schema R(MNPQ) and functional dependencies M→N, P→Q. Then the decomposition of R into R1(MN) and R2(PQ) is ............. (1) Dependency preserving but not lossless ... and lossless join (3) Lossless join but not dependency preserving (4) Neither dependency preserving nor lossless join.
Last Answer : Answer: 1
Description : For the complex [Fe(en)2Cl2], Cl, (en = ethylene diamine), identify (i) the oxidation number of iron, (ii) the hybrid orbitals and the shape of the complex, (iii) the magnetic behaviour of the complex, (iv) ... an optical isomer also, and (vi) name of the complex. (At. no. of Fe = 26) \ -Chemistry
Last Answer : i) [Fe(en)2Cl2] Cl or x + 0 + 2 (-1) + (-1) = 0 x + (- 3) = 0 or x = + 3 ∴ Oxidation number of iron, x = + 3 (ii) The complex has two bidentate ligands and two ... )2Cl2] Cl, only cis-isomer shows optical isomerism. (vi) Name of complex: Dichloridobis (ethane-1, 2- diamine) Iron (III) chloride
Description : [Fe(H2O)6]3+ is strongly paramagnetic whereas [Fe(CN)6]3- is weakly paramagnetic. Explain. (At. no. Fe = 26) -Chemistry
Last Answer : In both the cases, Fe is in oxidation state +3. Outer electronic configuration of Fe+3 is : In the presence of CN-, the 3d electrons pair up leaving only one unpaired electron. The ... sp3d2 forming an outer orbital complex. As it contains five unpaired electrons so it is strongly paramagnetic. .
Description : A complex compound in which the oxidation number of a metal is zero is - (1) K4 [Fe (CN)6] (2) K3 [Fe (CN)6] (3) [Ni (CO)4] (4) [Pl (NH3)4]Cl2
Last Answer : (3) [Ni (CO)4]
Description : The metal used to recover copper from a solution of copper sulfate is - (1) Na (2) Ag (3) Hg (4) Fe
Last Answer : (4) Fe Explanation: The metal used to recover copper from a solution of copper sulfate is Fe.
Description : The catalyst used in hydrogenation of oils is - (1) Fe (2) V2O5 (3) Ni (4) O2
Last Answer : (3) Ni Explanation: The catalyst used in hydrogenation of oils is nickel. It is used to speed up the reaction. Vegetable oils convert into vanaspati after hydrogenation.
Description : Which of the following metals is used in Space Crafts to withstand high temperatures? (1) Fe (2) Ti (3) Ni (4) Pb
Last Answer : (2) Ti Explanation: Titanium alloy, which has high corrosion resistance, high specific strength, and good heat resistance, is used for different spacecraft parts including outer fuel tank sheathing and wings. It is extremely strong at high temperatures.
Description : Which of the metallic ions is essential for blood clotting? (1) Na+ (2) Ca++ (3) K+ (4) Fe++
Last Answer : (2) Ca++ Explanation: Clotting also requires: calcium ions (Ca2+)(which is why blood banks use a chelating agent to bind the calcium in donated blood so the blood will not clot in the bag). about a dozen other protein clotting factors.
Description : Which of the following metals are present in hemoglobin and chlorophyll, respectively? (1) Fe and Mg (2) Fe and Zn (3) Mg and Zn (4) Zn and Mg
Last Answer : (1) Fe and Mg Explanation: Fe and Mg metals are present in hemoglobin and Chlorophyll respectively.
Description : Out of NaCl, MgSO4 , Al2 (SO4 ) 3 , K4 [Fe(CN)6 ], which one will bring about the coagulation of a gold sol quickest and in the least of concentration ?
Last Answer : Ans. Al2 (SO4 ) 3 .
Description : What happens when freshly precipitated Fe (OH)3 is shaken with a little amount of dilute solution of FeCl3 ?
Last Answer : Ans. It causes peptization leading to the formation of a positively charged sol of Fe (OH)3
Description : What is expected value of ‘i’ for K4[Fe(CN)6] in dilute solution?
Last Answer : Ans:- Expected value of n in K4(Fe(CN)6) is 5.
Description : Which of the following agents is used in order to make benzene react with bromine to give bromobenzene? (a) Ultraviolet light (b) Fe catalyst (c) Nickel catalyst (d) Al2O3 catalyst
Last Answer : Fe catalyst
Description : What is the % of H2O in Fe(CNS)3⋅3H2O [CPMT 1981] (A) 45 (B) 30 (C) 19 (D) 25
Last Answer : (C) 19
Description : Which of the following metals is used in Space Crafts to withstand high temperatures ? (1) Fe (2) Ti (3) Ni (4) Pb
Last Answer : Ti
Description : Can traffic violations prevent you from getting a state I.D in MN?
Last Answer : answer:For what length of time is your license suspended? If it’s not a permanent suspension, then you might not qualify for the ID until your suspension is over. What reason(s) has the state given you for not giving you an ID?
Description : How could, possibly, my friend get a ride from Rapid City, SD to Sioux Falls, SD or Minneapolis, Mn today?
Last Answer : Check out the bulletin board at any local college campus. Call the Library and Chamber of Commerce and ask if they know of community bulletin boards that might have ride-share info.
Description : Does anybody know of good campgrounds in the Virginia, MN area?
Last Answer : Do you mean the Virginia, Maryland area? You have Virginia, Minnesota area.
Description : Where in the Metro Area of MN, can I find a Body Mod artist (cutter)?
Last Answer : Does he really have to be cute? You mean, I think, a cutter…Sorry I can’t help. MN is a pretty conservative area.
Description : How do I obtain a MN state issued ID Card with only a Birth Certificate as form of ID verification?
Last Answer : Not sure if you can, check your local DMV. Here in Maine, in order to get your Driver’s License you have to have your SS card, your birth certificate and another form of picture ID- either an old license, Tribal ID or passport.
Description : What is the (MN) state and federal laws regarding the use of an alias on legal and puplic documents?
Last Answer : Whatever you heard once is highly unlikely to be still applicable since the changes implemented in the US following 9/11. If your drivers license lapses by even a fee weeks it's like starting all over ... and you'd better check all this out with the proper authorities and not rely on word of mouth.
Description : What are deer hunting season hours in mn?
Last Answer : Try this page.