Chemical - Phase - Ionic Equilibriums

The number of degrees of freedom in the homogenous liquid region of a two component system with a eutectic point, at one atmosphere pressure is:

The maximum number of triple point(s) occuring in one component sulfur system are:           

Choose correct:           

Consider the following equilibrium in a closed vessel  . At a fixed temperature if the volume of the reaction vessel is halved, which of the following statements holds true regarding the equilibrium constant (K_p) and the degree of dissociation (α) of N₂O₄?

Under conditions of constant temperature and pressure when a system is in equilibrium which of the following quantities is at a minimum:           

Based upon the following hypothetical equilibrium at 273 K

Which is the most effective dehydrating agent at 273 K (Aqueous tension at 273 K = 6.0 × 10^–3atm)

An equilibrium system for the reaction between hydrogen and iodine to give hydrogen iodine at 765 K in a 5 liter volume contains 0.4 mole of hydrogen, 0.4 mole of iodine and 2.4 moles of hydrogen iodide. The equilibrium constant for the reaction is:

To a 50 ml of 0.1 M HCl solution, 10 ml of 0.1 M NaOH is added and the resulting solution is diluted to 100 ml. What is change in pH of the HCl solution?           

To a 100 ml solution of 0.1 M CH₃COONa and 0.1 M CH₃COOH, 0.4 gm of solid NaOH was added. Assuming volume remains constant, calculate the change in pH value? Given that pK_a(CH₃COOH) = 4.74.           

When equal volumes of the following solution are mixed, precipitation of AgCl (K_sp = 1.8 × 10^–10) will occur only with:​

How many gram of CaC₂O₄ will dissolve in one litre of saturated solution? K_sp of CaC₂O₄ is 2.5 × 10^–9mol^–2 and its molecular weight is 128:           

Let the solubilities of AgCl in H₂O, 0.01 M CaCl₂; 0.01 M NaCl and 0.05 M AgNO₃ be S₁, S₂, S₃, S₄ respectively. What is the correct relationship between these quantities?           

 Calculate the minimum mole % of CO₂ in air at 1 bar which is sufficient to prevent any loss in weight of Ag₂CO₃ by decomposition at the same temperature:

At temperature T, a compound AB₂(g) dissociates according to the reaction  with degree of dissociation α, which is small compared with unity. The expression for K_p, in terms of α and the total pressure, P_T is:

A reaction mixture containing H₂, N₂ and NH₃ has partial pressures 2 atm, 1 atm and 3 atm respectively at 725 K. If the value of Kp for the reaction.  is4.28 × 10^–5atm^–2 at 725 K, in which direction the net reaction will go:           

pH of an aqueous solution of Al⁺³ is likely to be:           

The molar solubility (in mol L^–1) of a sparingly soluble salt MX₄ is ‘s’. The corresponding solubility product is K_sp. s is given in terms of K_sp by the relation:

The phase diagram of a pure substance is sketched below:

The number of degrees of freedom at points P1, P2 and P3, respectively, are:

Consider a phase diagram of two component simple eutectic system. If X_A = 0.8 and X_B = 0.2, which of the following composition will never be observed:           

The number of phases, components and degrees of freedom, when Ar is added to an equilibrium mixture of NO, O₂ and NO₂ in gas phase are, respectively:           

A pure substance exists in several different phases A, B, C. Its partial phase diagram is shown below: 
          
Which of the following statements is correct about the above diagram?           

The lowest pressure at which the liquid phase of a pure substance can exist is known as:           

The solid-liquid phase diagram for the Mg-Zn system is shown in the figure below where the vertical line at X(Mg) = 0.33 represents the formation of a congruent melting compound MgZn₂.The figure is divided into seven regions depending upon the physical state of the system. The composition of the region #6 represents.

Which of the following does not represent a phase diagram?

For the reaction  the degree of dissociation (α) of HI(g) is related to equilibrium constant K_p by the expression:

Choose correct:          

Solid CO₂ is called ‘dry ice’ because:           

pH of the following solution is not affected by dilution:           

In the following reaction:

 

When HCl(g) is passed through a saturated solution of common salt, pure NaCl is precipitated because:           

Choose the correct statement/s:           

Choose correct statement/s:           

Formation of Y from X is through the graph. It can be concluded:

The expression for the equilibrium constant for an ideal-gas reaction mixture is given by:

With a certain radiation (exciting) of a particular frequency, to which hydrogen atoms are exposed, the maximum number of spectral lines is obtainable in the emission is 15. The uppermost energy level to which the is excited is n =

Benzene and naphthalene form an ideal solution at room temperature. For this process, the true statement(s) is/are:

Which of the following statements are incorrect:           

When baking soda is heated in a sealed tube, following equilibrium exists: 
 
If the equilibrium pressure is 1.04 atm at 398 K, calculate the equilibrium constant for the reaction at 398 K [up to two decimal places]:

16 moles of H₂ and 4 moles of N₂ are sealed in a one litre vessel. The vessel is heated at a constant temperature until the equilibrium is established, it is found that the pressure in the vessel has fallen to 9/10 of its original value. Calculate K_C for the reaction. [In the multiple of 10^–4 up to two decimal places]:

How many milli-moles of Ca(OH)₂ must be dissolved to produce 250 mL of an aqueous solution of pH 10.65, assuming complete dissociation?  [up to two decimal places]

For a pure substance, lnP_(solid) = –20/T + 10 and lnP_(liquid) = –15/T + 2. Calculate enthalpy of fusion. [In the multiple of R]

Among CO₂, Sulfur, Water, Antimony, Bismuth how many have (dp/dT)_fusion is negative?

At 0°C, ∆H_fusion(ice) = 1092 Kcal/mol. The molar entropy change for melting of ice at 0°C is? (in kcal/Kmol, up to two decimal places)

Find out amount (in gram, up to first decimal place) of NH₄Cl dissolved in 500 mL to have pH = 4.5. K_b for NH₄OH is 1.8 × 10^–5.

Calcium lactate is a salt of weak organic acid and strong base, represented as Ca(Lac)₂. A saturated solution of Ca(Lac)₂ contains 0.13 mole of this salt in 0.50 L solution. The pOH of this solution is 5.60. Assuming a complete dissociation of the salt, calculate K_a of lactic acid. [In the multiple of 10^–4, up to first decimal place]

The self-ionization constant for pure formic acid, K = [HCOOH₂⁺] [HCOO^–] has been estimated as 10^–6 at room temperature. What percentage of formic acid molecules in pure formic acid are converted to formate ion? The density of formic acid is 1.22 g/cm³. [rounded up to four decimal places]

Calculate the pH of solution obtained by mixing 10 mL of 0.1 M HCl and 40 of 0.2 M H₂SO₄? [up to two decimal places]

A sample of HI was found to be 22% dissociated when equilibrium was reached. What will be the degree of dissociated if hydrogen is added in the proportion of 1 mole for every mole of HI originally present, the temperature and volume of the system being kept constant: [up to two decimal places]

The pH of pure water at 25°C and 35°C are 7 and 6 respectively. Calculate the heat of formation (cal/mol, up to first decimal place) of water from H⁺ and OH^–?

Calculate pH change when 0.01 mol CH₃COONa solution is added to one litre of 0.01 CH₃COOH solution. [up to two decimal places]
K_a (CH₃COOH) = 1.8 × 10^–5, pK_a = 4.74

50 mL of 0.1 M NaOH is added to 75 mL of 0.1 M NH₄Cl to make a basic buffer. If pK_a of NH₄⁺ is 9.26, Calculate pH (up to two decimal places)?

K_c for the equilibrium reaction N₂O₄ dissociating into 2NO₂ in chloroform at 291K is 1.14. Calculate free energy change of reaction (Latm) when concentration of two gases are 0.5 mol/L each at same temp. (R = 0.082 LatmK^–1mol^–1, up to two decimal places)

The degree of dissociation at a certain temp of PCl₅ at 2 atm is found to be 0.4. At what pressure, the degree of dissociation of PCl₅ will be 0.6 at same temp: [up to two decimal places]

The vapor density of a mixture containing NO₂ and N₂O₄ is 38.3 at 26.7⁰C. Calculate no of moles of NO₂ in 100g mixture: [up to three decimal places]

An aqueous system containing K⁺, Na⁺, Cl^– what are number of components if salts are present in equal amount?

3 phases are in equilibrium for which T and P can be independently changed at constant composition. Calculate components (C):

For a pure substance, lnP_(solid) = –20/T + 10 and lnP_(liquid) = –15/T + 2. Calculate ratio of slope at triple point [up to two decimal places]: