Basic Concepts in Chemistry
2C57H110O6(s) + 163 O2(g) → 114CO2(g) + 110H2O(l)
(Atomic weights in g mol–1: O = 16, S = 32, Pb = 207)
MnCl2 + K2S2O8 + H2O → KMnO4 + H2SO4 + HCl (equation not balanced).
Few drops of concentrated HCl were added to this solution and gently warmed. Further, oxalic acid (225 mg) was added in portions till the colour of the permanganate ion disappeared. The quantity of MnCl2 (in mg) present in the initial solution is ____.
(Atomic weights in g mol−1: Mn = 55, Cl = 35.5)
(Hint: Allene is 1,2-propadiene i.e. H2C = C = CH2)
|Column I||Column II|
|(Molecules)||(Number of lone pairs on central atom)|
Which of the following statements is correct for a liquid and its vapour at boiling point?
How can the paths given in List I be correctly matched with the magnitudes of the work done in List II?
|List I||List II|
|P.||C → A||1.||24P0V0 [3ln2 + ln3]|
|Q.||C → D||2.||23 P0V0|
|R.||B → C||3.||17.2 P0V0|
Given: log 2 = 0.3010, log 3 = 0.4771
Given: log 2 = 0.3010, log 7 = 0.8451, log 3 = 0.4771
N2O4 (g) 2 NO2 (g)
At 55 °C and 1 atm, the percentage decomposition of N2O4 is 40. At what pressure (p) the equilibrium mixture will have the ratio N2O4 : NO2 as 1 : 8?
In a second experiment (Experiment 2), 100 mL of 2.0 M acetic acid solution (Ka = 2.0 × 10−5) was mixed with 100 mL of 2.0 M NaOH solution (under identical conditions as in Experiment 1) where a temperature rise of 11.2 °C was measured. (Consider heat capacity of all solutions as 4.2 J g−1 K−1 and density of all solutions as 1.0 g mL−1)
Magnitude of enthalpy of dissociation (in kJ mol−1) of acetic acid obtained from the Experiment 2 is
(Given: ΔfG° values of CH4(g) = − 693.5 kJ mol−1 , CO2 (g) = −421.2 kJ mol−1 and H2O(l) = −227.4 kJ mol−1, antilog (0.98) = 9.65)
(At. Wt.: Mg = 24)
(Ag = 107.8, N = 14, O = 16, Na = 23 and Cl = 35.5)
(At. wt. Mg = 24; O = 16)
6.02 × 1020 molecules of urea are present in 100 mL of its solution. The concentration of solution is :
A compound with molecular mass 180 is acylated with CH3COCl to get a compound with molecular mass 390. The number of amino groups present per molecule of the former compound is :
A gaseous hydrocarbon gives upon combustion 0.72 g. of water and 3.08 g. of CO2. The empirical formula of the hydrocarbon is :
How many litres of water must be added to 1 litre of an aqueous solution of HCl with a pH of 1 to create an aqueous solution with pH of 2 ?
Experimentally it was found that a metal oxide has formula M0.98O. Metal M, is present as M2+ and M3+ in its oxide. Fraction of the metal which exists as M3+ would be :
How many grams of concentrated nitric acid solution should be used to prepare 250 mL of 2.0M HNO3? The concentrated acid is 70% HNO3.
25 mL of household bleach solution was mixed with 30 mL of 0.50 M KI and 10 mL of 4N acetic acid. In the titration of the liberated iodine, 48 mL of was used to reach the end point. The morality of the household bleach solution is
Assertion : Equal moles of different substances contain same number of constituent particles.
Reason : Equal weights of different substances contain the same number of constituent particles.
Dissolving 120g of urea (mol.wt 60) in 1000g of water gave a solution of density 1.15g/mL. The molarity of the solution is
480 mL of 1.5 M first solution +520 mL of 1.2 M second solution.
What is the molarity of the final mixture?
The volume (in mL) of 0.1M AgNO3 required for complete precipitation of chloride ions present in 30mL of 0.01 M solution of as silver chloride is close to
Reason : The molarity of a solution depends upon the density of the solution whereas molality does not.
A student performs a titration with different burettes and finds titre values of 25.2 mL, 25.25mL and 25.0mL. The number of significant figures in the average titre value is
Silver (atomic weight = 108gmol-1) has a density of 10.8 gcm-3 . The number of silver atoms on a surface of area can be expressed in scientific notation as The value of x is
The Henry’s law constant for the solubility of N2 gas in water at is . The mole fraction of N2 in air is 0.8. The number of moles of N2 from air dissolved in 10 moles of water at 298K and 5 atm pressure is
Reason H2C2O4.2H2O is a dihydrate organic acid.
(A) 6.023 × 1023
(B) 1/9.108 × 1031
(C) 6.023/9.108 × 1054
(D) 1/(9.108 × 6.023) × 108
(a) 40 ml
(b) 20 ml
(c) 10 ml
(d) 4 ml