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Engineering
3 months, 2 weeks ago

In a vessel, the gas is at a pressure P. If the mass of all the molecules is halved and their speed is doubled, then the resultant pressure will be:

  • Option 1)

    4P

  • Option 2)

    2P

  • Option 3)

    P

  • Option 4)

    \frac{P}{2}

 

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S solutionqc
Answered 3 months, 2 weeks ago
Pressure of a gas if mass is halved and speed is doubled pressure becomes 2P Option 1) 4P Option 2) 2P Option 3) P Option 4)
Engineering
3 months, 3 weeks ago

A reaction having equal energies of activation for forward and reverse reactions has:

  • Option 1)

    \DeltaH = \DeltaG = \DeltaS=0

  • Option 2)

    \DeltaS = 0

  • Option 3)

    \DeltaG = 0

  • Option 4)

    \DeltaH = 0

 

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S SudhirSol
Answered 3 months, 3 weeks ago
Option 1) H = G = S=0 Option 2) S = 0 Option 3) G = 0 Option 4) H = 0
Engineering
84 Views   |   7 months, 1 week ago

The most popularly known blood grouping is the ABO grouping. It is named ABO and not ABC, because "O" in it refers to having:

  • Option 1)

    overdominance of this type on the genes for A and B types

  • Option 2)

    one antibody only - either anti-A or anti-B on the RBCs

  • Option 3)

    no antigens A and B on RBCs

  • Option 4)

    other antigens besides A and B on RBCs

 

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A arpit
Answered 7 months ago

3 option

 

Engineering
56 Views   |   11 months ago

The Gibbs energy for the decomposition of Al2O3 at 500oC is as follows:

\frac{2}{3}\text{Al}_{2}\text{O}_{3}\rightarrow \frac{4}{3}\text{Al}+\text{O}_{2};

\Delta_{\text{r}}\text{G}=+960 \text{kJ} \text{mol}^{-1}.

The potential difference needed for the electrolytic reduction of aluminium oxide (Al2O3) at 500oC is at least:

  • Option 1)

    3.0 V

  • Option 2)

    2.5 V

  • Option 3)

    5.0 V

  • Option 4)

    4.5 V

 
Engineering
42 Views   |   11 months ago

The enthalpy of fusion of water is 1.435 kcal/mol. The molar entropy change for the melting of ice at 0°C is :

  • Option 1)

    10.52 cal / (mol K)

  • Option 2)

    21.04 cal / (mol K)

  • Option 3)

    5.260 cal / (mol K)

  • Option 4)

    0.526 cal / (mol K)

 
Engineering
51 Views   |   11 months ago

In which of the following reactions, standard reaction entropy change (\DeltaS°) is Positive and standard Gibbs energy change (\DeltaG°) decreases sharply with increasing temperature?

  • Option 1)

    \text{C}\ \text{graphite}+\frac{1}{2}\text{O}_{2(\text{g})}\rightarrow \text{CO}_{(\text{g})}

  • Option 2)

    \text{CO}_{(\text{g})}+\frac{1}{2}\text{O}_{2(\text{g})}\rightarrow \text{CO}_{2(\text{g})}

  • Option 3)

    \text{Mg}_{(\text{s})}+\frac{1}{2}\text{O}_{2(\text{g})}\rightarrow \text{MgO}_{(\text{s})}

  • Option 4)

    \frac{1}{2}\text{Cgraphite}+\frac{1}{2}\text{O}_{2(\text{g})}\rightarrow\frac{1}{2} \text{CO}_{2(\text{g})}

 
Engineering
60 Views   |   11 months ago

Equal volumes of two monoatomic gases A and B, at same temperature and pressure are mixed. The ratio of specific heats (Cp/Cv) of the mixture will be:

  • Option 1)

    1.50

  • Option 2)

    3.3

  • Option 3)

    1.67

  • Option 4)

    0.83

 
Engineering
82 Views   |   11 months, 1 week ago

Which of the following is/are the hazardous pollutants present in automobile exhaust gases?

1) N_{2}

2) CO

3) CH_{4}

4) Oxides of nitrogen

 

  • Option 1)

    2 & 3

  • Option 2)

    1 & 2

  • Option 3)

    2 & 4

  • Option 4)

    1 & 3

 

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A aadil.khan
Answered 11 months ago
As we learned @1825   Co and oxides of nitrogen gases are emitted as a result of the combustion of fuels. Option 1) 2 & 3 Option 2) 1 & 2 Option 3) 2 & 4 Option 4) 1 & 3
Engineering
100 Views   |   1 year ago

Which one of the alkali metals, forms only, the normal oxide, M_{2}O on heating in air?

  • Option 1)

    Rb

  • Option 2)

    K

  • Option 3)

    Li

  • Option 4)

    Na

 

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B balakrishnan m
Answered 1 year ago

Li

 

Engineering
106 Views   |   1 year ago

Which of the following oxides is not expected to react with sodium hydroxide?

  • Option 1)

    C_{a}O

  • Option 2)

    S_{i}O_{2}

  • Option 3)

    B_{e}O

  • Option 4)

    B_{2}O_{3}

 

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V Vakul Arora
Answered 1 year ago
As learnt Alkaline earth metals - Elements of Group 2 of the periodic table Be, Mg, Ca, Sr, Ba, Ra - wherein Their oxides are alkaline except Be    The oxides of alkaline earth metals are basic (except BeO) and basic oxides don't react with NaOH which also is basic. Option 1) This option is correct Option 2) This option is incorrect Option 3) This option is incorrect Option 4) This option...
Engineering
125 Views   |   1 year ago

Structures of some common polymers are given. Which one is not correctly presented?

  • Option 1)

    Neoprene

  • Option 2)

    Terylene

  • Option 3)

    Nylon

  • Option 4)

    Teflon

 

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V Vakul Arora
Answered 1 year ago
As we learnt in  Neoprene - - Formed by free radical polymerization of chloroprene ( 2-chloro-1, 3-butadiene ). - Homopolymer - wherein - Superior resistance to vegetable and mineral oils. - Used in manufacturing conveyor belts, gaskets, hoses.   Neoprene is a polymer of chloroprene. structure Option 1) Correct Option 2) Incorrect Option 3) Incorrect Option 4) Incorrect
Engineering
100 Views   |   1 year ago

The number of octahedral void (s) per atom present in a cubic close-packed structure is:

  • Option 1)

    1

  • Option 2)

    3

  • Option 3)

    2

  • Option 4)

    4

 

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V Vakul Arora
Answered 1 year ago
As learnt in Voids - Voids are empty spaces in a unit cell. They are of four types: triangular, tetrahedral, octahedral, cubic. -    We know that the no. of actohedral voids in a close packed structure = no. of atoms for a cubic close packed structure, no. of atoms = 1  octahedral voids = 1   Option 1) 1 this option is correct Option 2) 3 this option is incorrect Option 3) 2 this option is...
Engineering
174 Views   |   1 year ago

The Number of Carbon atoms per unit cell of diamond unit cell is :

  • Option 1)

    8

  • Option 2)

    6

  • Option 3)

    1

  • Option 4)

    4

 

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A aadil.khan
Answered 1 year ago
As we learnt in  Diamond unit all is FCC with 4 atoms additionally bonded tetrahedrally which have full contribution to the all.  So, no.of atoms                               Option 1) 8 this option is correct Option 2) 6 this option is incorrect Option 3) 1 this option is incorrect Option 4) 4 this option is incorrect
Engineering
339 Views   |   1 year ago

Lithium metal crystallises in a body centered cubic crystal. If the length of the side of the unit cell of lithium is 351 pm.the atomic radius of the lithium will be:

  • Option 1)

    151.8 pm

  • Option 2)

    75.5 pm

  • Option 3)

    300.5 pm

  • Option 4)

    240.8 pm

 

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P prateek
Answered 1 year ago
As learnt in Relation between radius of constituent particle, R and edge length, a for body centered cubic unit cell - -    for a BCC lattice, we know that   Option 1) 151.8 pm this option is correct Option 2) 75.5 pm this option is incorrect Option 3) 300.5 pm this option is incorrect Option 4) 240.8 pm this option is incorrect
Engineering
102 Views   |   1 year ago

In Castner-Kellner cell for production of sodium hydroxide:

  • Option 1)

    Brine is electrolyzed with Pt electrodes

  • Option 2)

    Brine is electrolyzed using graphite electrodes

  • Option 3)

    Molten sodium chloride is electrolyzed

  • Option 4)

    Sodium amalgam is formed at mercury cathode

 

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P prateek
Answered 1 year ago
As we learnt in Preparation of NaOH by castner-Kellner cell - Also known as mercury cathode process by electrolysis of aq.solution of brine cathode:   Anode: - wherein Cell comprises of three compartments Outer compartment:Brine solution is electrolysed Central compartment: 2% NaOH solution and     In the Castner Kellner cell,  At cathode,  At anode,  Sodium Amalgam is formed at...
Engineering
142 Views   |   1 year ago

Copper crystallises in a face-centered cubic lattice with a unit cell length of 361 pm.What is the radius of copper atom in pm?

  • Option 1)

    157

  • Option 2)

    181

  • Option 3)

    108

  • Option 4)

    128

 

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P perimeter
Answered 1 year ago
For an FCC lattice, we know  Option 1) 157 this option is incorrect Option 2) 181 this option is incorrect Option 3) 108 this option is incorrect Option 4) 128 this option is correct
Engineering
147 Views   |   1 year ago

A metal crystallizes with a face-centered cubic lattice. The edge length of the unit cell is 408 pm. The diameter of the metal atom is:

  • Option 1)

    288 pm

  • Option 2)

    408 pm

  • Option 3)

    144 pm

  • Option 4)

    204 pm

 

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P Plabita
Answered 1 year ago
For an FCC, where r= radius of atom a= edge length Option 1) 288 pm This option is correct Option 2) 408 pm This option is incorrect Option 3) 144 pm This option is incorrect Option 4) 204 pm This option is incorrect
Engineering
120 Views   |   1 year ago

What is the density of N_{2} gas at 227^{o}C and 5.00 atm pressure? (R=0.0821 atm K^{-1} mol^{-1})

  • Option 1)

    0.29 g/ml

  • Option 2)

    1.40 g/ml

  • Option 3)

    2.81 g/ml

  • Option 4)

    3.41 g/ml

 

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A aadil.khan
Answered 1 year ago
  Ideal Gas Law - - wherein P - Pressure V - Volume n - No. of Moles R - Gas Constant T - Temperature     Ideal Gas Law in terms of density - - wherein where d - density of gas P - Pressure R - Gas Constant T - Temperature M - Molar Mass      from ideal gas equation  Pv=nRT or PM=RT = Option 1) 0.29 g/ml This option is incorrect  Option 2) 1.40 g/ml This option is incorrect  Option 3) 2.81...
Engineering
256 Views   |   1 year ago

Which condition is not satisfied by an ideal solution?

  • Option 1)

    \Delta _{mix}H=0

  • Option 2)

    \Delta _{mix}V=0

  • Option 3)

    \Delta _{mix}S=0

  • Option 4)

    Obeyance to Raoult's Law

 

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P prateek
Answered 1 year ago
As learnt Condition of ideality - Interaction between A - A; B - B are similar to A - B Interactions. eg. Hexane + Heptone Benzene + Toluere - wherein       Conditions for ideality for a solution are: Also, an ideal solution always Raoult's Law Option 1) This option is incorrect Option 2) This option is incorrect Option 3) This option is correct Option 4) Obeyance to Raoult's Law This...
Engineering
110 Views   |   1 year ago

The values of \Delta H \ and \ \Delta S for the reaction, C_{\left ( graphite \right )}+CO_{2}_{\left ( g \right )}\rightarrow 2CO_{\left ( g \right )}  are 170kJ and 170JK^{-1}, respectively. The reaction will be spontaneous at

  • Option 1)

    910K

  • Option 2)

    1110K

  • Option 3)

    510K

  • Option 4)

    710K

 

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S subam
Answered 1 year ago
  Gibb's free energy (? G) -   - wherein Gibb's free energy enthalpy of reaction entropy temperature    For the reaction to be spontaneous given is -Ve only when which is possible only at ie. reaction will be spontaneous P= V=.03m3 P Option 1) 910K Incorrect Option Option 2) 1110K Correct Option Option 3) 510K Incorrect Option Option 4) 710K Incorrect Option
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