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Engineering
132 Views   |  

The formation of these phosgene is represented as , CO\ + Cl_2\ \leftrightarrow COCl_2 . The reaction is carried out in 500 ml flask . At equilibrium 0.3 mole of phosgene , 0.1 mole of CO and 0.1 mole of Cl2 are present. The equlibrium constant of the reaction is :

 

  • Option 1)

    30

  • Option 2)

    15

  • Option 3)

    5

  • Option 4)

    3

 
As we learned in concept Law of Chemical equilibrium - At a given temperature, the product of concentration of the reaction products raised to the respective stoichiometric coefficient in the balanced chemical equation divided by the product of concentration of the reactants raised to their individual stoichiometric coefficients has a constant value. - wherein are equilibrium...
Engineering
101 Views   |  

The equlibrium constant for  H_2 (g) + CO_2 (g) \leftrightarrow H_2O(g) + CO(g)  is 1.80 at  1000 *C .If 1 mole of H2 and 1 mole of Co2 are placed in one litre flask, the final equilibrium concentration of CO at 1000*C will be

  • Option 1)

    0.573 M

  • Option 2)

    0.385 M

  • Option 3)

    5.73 M

  • Option 4)

    0.295 M

 
As we learned in concept Law of Chemical equilibrium - At a given temperature, the product of concentration of the reaction products raised to the respective stoichiometric coefficient in the balanced chemical equation divided by the product of concentration of the reactants raised to their individual stoichiometric coefficients has a constant value. - wherein are equilibrium...
Engineering
91 Views   |  

The density of NH_{4}OH solution is 0.6 g/ml. It contains 35% by weight of NH_{4}OH. Calculate the normality of the solution

  • Option 1)

    4.8N

  • Option 2)

    10N

  • Option 3)

    0.5N

  • Option 4)

    6.0N

 
As we learned in concept Molarity - -    for NH4OH, Molarity =normality   means 35g NH4OH in  100g of solution =   Option 1) 4.8N Option is incorrect Option 2) 10N Option is incorrect Option 3) 0.5N Option is incorrect Option 4) 6.0N Option is correct
Engineering
92 Views   |  

The degree of dissociation of PCl5(\alpha) obeying the equilibrium, PCl5(g) \leftrightarrowPCl3(g) + Cl2(g) is approximately related to the pressure at equilibrium by  

  • Option 1)

    \alpha ∝ P

  • Option 2)

    \alpha ∝ \frac{1}{\sqrt{p}}

  • Option 3)

    \alpha ∝\frac{1}{p^{2}}

  • Option 4)

    \alpha ∝ \frac{1}{p^{4}}

 
As we learnt in Equilibrium constant in gaseous system - For equilibrium involving gases, it is usually more convenient to express the equilibrium constant in terms of partial pressure.  - wherein The ideal gas equation is written as     Let's consider the given reaction                                     Total pressure =P     Option 1)  ∝ P This option is incorrect Option...
Engineering
91 Views   |  

Pure water is kept in a vessel and it remains exposed to atmospheric CO2 which is absorbed, then the PH will be:

  • Option 1)

    Greater than 7

  • Option 2)

    Less than 7

  • Option 3)

    7

  • Option 4)

    Depends on ionic product 

 
As learnt in Vapour Pressure - It is defined as pressure exerted by vapours on liquid surface at equilibrium and condensation. -    CO2  will dissolve in water forming carbonic acid (H2CO3) which will drop the pH of the solution below 7.   Option 1) Greater than 7 Incorrect Option 2) Less than 7 correct Option 3) 7 Incorrect Option 4) Depends on ionic product  Incorrect
Engineering
324 Views   |  

Number of gram equivalents present per litre of solution in a semi normal solution is

  • Option 1)

    \frac{1}{2}

  • Option 2)

    \frac{1}{5}

  • Option 3)

    \frac{1}{10}

  • Option 4)

    \frac{1}{100}

 
As we learnt in Molarity - -    A solution that has one gram equivalent of solute in one litre of solution is called one normal. Similarly a semi normal solution contains  1/2g equivalent solute per litre of solution.   Option 1) correct Option 2) Incorrect Option 3) Incorrect Option 4) Incorrect
Engineering
98 Views   |  

Low concentration of oxygen in the blood and tissues of people living at high altitude is due to     

  • Option 1)

    Low temperature 

  • Option 2)

    Low atmospheric pressure

  • Option 3)

    High atmospheric pressure 

  • Option 4)

    Both low temperature and high atmospheric pressure 

 
As learnt in Relation between pressure and concentration - - wherein P is pressure in Pa. C is concentration in mol / litre. T is temperature in kelvin     At higher altitudes, the pressure decreases causing a lowering in concentration of oxygen in the blood as P =CRT   Option 1) Low temperature  Incorrect Option 2) Low atmospheric pressure correct Option 3) High atmospheric...
Engineering
141 Views   |  

Kfor m1A + m2B = n1C + n2D is given by:

  • Option 1)

    Kc = \frac{[A]^{m_{1}}[B]^{m_{2}}}{[C]\times [D]}

  • Option 2)

    Kc = \frac{[A]^{m_{1}}[B]^{m_{2}}}{[C^{m_{1}}]\times [D]^{m_{2}}}

  • Option 3)

    Kc = \frac{[C]^{n_{1}}[D]^{n_{2}}}{[A]^{m_{1}}\times [B]^{m_{2}}}

  • Option 4)

    Kc = \frac{[C]^{n_{1}}[D]^{n_{2}}}{[A]^{n_{1}}\times [B]^{n_{2}}}

 
As we learnt in Law of Chemical equilibrium - At a given temperature, the product of concentration of the reaction products raised to the respective stoichiometric coefficient in the balanced chemical equation divided by the product of concentration of the reactants raised to their individual stoichiometric coefficients has a constant value. - wherein are equilibrium concentration   m1A +...
Engineering
93 Views   |  

In an aqueous solution of volume 500 ml , when the reaction of  2Ag^+\ +\ Cu \leftrightarrow Cu^2^+\ +\ 2Ag  reached equilibrium the [Cu2+] was x Molar . When 500 ml of water is further added , the equilibrium [Cu2+] will be :

  • Option 1)

    2x M

  • Option 2)

    x M

  • Option 3)

    between x M and x/2 M

  • Option 4)

    less than x/2 M

 
As we learnt in Le Chatelier's Principle - It states that a change in any of the factors that determine the equilibrium condition of a system will cause the system to change in such a manner to reduce or to counteract the effect of change. -   According to Le Chatelier's principle, the equilibrium will shift in a direction so as to counteract the effects of the changes. As the solution dilutes,...
Engineering
393 Views   |  

If 0.1 mole of I2, is introduced into 1 litre flask at 1000 k, at equilibrium (Kc = 10-6), which one is correct? 

  • Option 1)

    [ I2 (g) ] > [I (g)]

  • Option 2)

    [I2 (g)] < [1 (g)]

  • Option 3)

    [I2 (g)] = [ 1(g) ]

  • Option 4)

    [I(g)] = \frac{1}{2}[I (g)]

 
As we learnt in Law of Chemical equilibrium - where  A & B are the reactants, C & D are the product in balanced chemical equations. - wherein Kc is the equilibrium constant.    The reaction takes place as follows Clearly, the equilibrium constant favours      Option 1) [ I2 (g) ] > [I (g)] correct Option 2) [I2 (g)] < [1 (g)] incorrect Option 3) [I2 (g)] = [ 1(g) ] incorrect Option...
Engineering
91 Views   |  

Henry's Law at constant temperature states that  

  • Option 1)

    The solubility of gas in a liquid is directly proportional to the partial pressure of gas in solution.

  • Option 2)

    Mole fraction of gas in solution is proportional to partial pressure of gas over solution 

  • Option 3)

    Partial pressure of gas in vapour phase is proportional to mole fraction of gas in solution

  • Option 4)

    All of these

 
As learnt in Henry's Law - It decides the solubility of gases in liquids. = mole fraction of gas in liquid. = Partial pressure of gas over liquid surface. -    Henry's law states that solubility of a gas in a liquid is directly proportional to partial pressure of gas. All the other options can be implied from above. Option 1) The solubility of gas in a liquid is directly proportional to...
Engineering
115 Views   |  

For the equilibrium, PCl\leftrightarrow PCl3 + Cl2

K_{c}=\frac{\alpha ^{2}}{(1-\alpha )v}, temperature remaining constant:

  • Option 1)

    Kc will increase with the increase in volume

  • Option 2)

    Kc will increase with the decrease in volume.

  • Option 3)

    Kc will not change with the change in volume

  • Option 4)

    Kc may increase or decrease with the change in volume

 
As learnt in Features of equilibrium constant - Equilibrium constant is temperature dependent  having one unique value for a particular reaction represented by a balanced equation at a given temperature. -    Equilibrium constant is temperature dependent having a unique value at each temperature. It will not change with volume. Option 1) Kc will increase with the increase in volume This...
Engineering
177 Views   |  

Expression P=P= x1Pi (P is total vapour pressure) holds good for binary solution containing 

  • Option 1)

    CHCl3 and CH2Cl2

  • Option 2)

    Nacl and H2O

  • Option 3)

    MeOH and H2O

  • Option 4)

    EtOH  and CH3COCH3

 
As learnt in  Rault's Law - The total vapour pressure of binary mixture of miscible liquids be having ideally is given by Where   and  are mole fraction of A and B in liquid phase.     - wherein   and are vapour pressures of pure liquids.    The expression given in Raoult's law but it is only valid for liquids that do not interact. Only NaCl and H2O fulfill that condition. Option 1) CHCl3...
Engineering
167 Views   |  

An aqueous solution of 2% non-volatile solute exerts pressure of 1.004 bar at the normal boiling point of solvent. The molar mass of the solute is g/mol is    

  • Option 1)

    85.42

  • Option 2)

    41.35

  • Option 3)

    90

  • Option 4)

    94.42

 
As learnt in Rault's Law - The total vapour pressure of binary mixture of miscible liquids be having ideally is given by Where   and  are mole fraction of A and B in liquid phase.     - wherein   and are vapour pressures of pure liquids.     Option 1) 85.42 This option is incorrect Option 2) 41.35 This option is correct Option 3) 90 This option is incorrect Option 4) 94.42 This option is...
Engineering
227 Views   |  

An aqueous solution contains a substance which yeilds 4x10-3 mol/l ion of H3O+. If log 2=0.3010 then PH of the solution is:

  • Option 1)

    1.5

  • Option 2)

    2.398

  • Option 3)

    3.0

  • Option 4)

    3.4

 
As learnt in The p(H) scale - Hydronium ion concentration in molarity is more conveniently expressed on a logarithmic scale known as p(H) scale. - wherein The p(H) of a solution is defined as negative logarithm to base 10 of the activity of hydrogen ion     then                                          Option 1) 1.5 This answer is incorrect Option 2) 2.398 This answer is correct Option...
Engineering
122 Views   |  

An 0.8M solution of ethanol has density 0.99gcm^{-3}. The molality of the solution is

  • Option 1)

    0.8

  • Option 2)

    Less than 0.8

  • Option 3)

    0.84

  • Option 4)

    0.4

 
As learnt in Molality - -    We know,  m1 = molar mass of solute M = Molarity d = density of solution m = molality   we have,                              = 0.84 Option 1) 0.8 This answer is incorrect Option 2) Less than 0.8 This answer is incorrect Option 3) 0.84 This answer is correct Option 4) 0.4 This answer is incorrect
Engineering
580 Views   |  

A weak acid after treatment with 12ml of 0.1m strong base BOH has a PH of 5. At the end point, the volume of same base required is 26.6ml Ka of acid is 

  • Option 1)

    1.8x10-15

  • Option 2)

    8.12x10-6

  • Option 3)

    1.8x10-6

  • Option 4)

    18.2x10-5

 
As learnt in Buffer Solutions - The solutions which resist change in pH on dilution or with addition of small amounts of acid or alkali are called buffer solution.   - wherein Many body fluids  e.g.  blood    Total milliequivalents of acid = milliequivalents of base                 = 26.6 x 0.1 = 2.66 But the resultant mixture has HA left The reaction is as follows:             HA    +   ...
Engineering
107 Views   |  

A gaseous phase reaction is allowed to attain equilibrium as , A (g) \leftrightarrow B (g) + C (g)  at constant Pressure 'P' . The partial pressure of A at equilibrium is \frac{P}{2} . The value of equilibrium constant KP is 

  • Option 1)

    \frac{P}{2}

  • Option 2)

    \frac{P}{4}

  • Option 3)

    \frac{P}{6}

  • Option 4)

    \frac{P}{8}

 
As learnt in Equilibrium constant in gaseous system - For equilibrium involving gases, it is usually more convenient to express the equilibrium constant in terms of partial pressure.  - wherein The ideal gas equation is written as                                          at equilibrium                                      x              x Total pressure at equilibrium = P Option 1) This...
Engineering
270 Views   |  

A buffer mixture of acetic acid and potassium acetate has PH=5.24. The ratio of [CH3COO-]/[CH3COOH] in this buffer is, (pKa=4.74)

  • Option 1)

    3:1

  • Option 2)

    1:3

  • Option 3)

    1:1

  • Option 4)

    1:2

 
As learnt in Buffer Solutions - The solutions which resist change in pH on dilution or with addition of small amounts of acid or alkali are called buffer solution.   - wherein Many body fluids  e.g.  blood     for a buffer solution of weak acid and it's salt Option 1) 3:1 This option is correct Option 2) 1:3 This option is incorrect Option 3) 1:1 This option is incorrect Option 4) 1:2 This...
Engineering
348 Views   |  

4L of 0.02 M aqueous solution of Nacl was diluted by adding one litre of water. The molarity of the resultant  solution  is  

  • Option 1)

    0.004

  • Option 2)

    0.008

  • Option 3)

    0.012

  • Option 4)

    0.016

 
As learnt in Molarity - -    Number of moles of NaCl = 4 x 0.02 = 0.08 Total final volume = 5 L M = 0.08 / 5 = 0.016 M Option 1) 0.004 This option is incorrect Option 2) 0.008 This option is incorrect Option 3) 0.012 This option is incorrect Option 4) 0.016 This option is correct
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