A 10 liter container consist of 1 mole of gas at 300 K. It is connected to another container having volume 40 liter and is initially at 300 K. The nozzle connecting two containers is opened for a long time and once the movement of gas stopped, the larger container was heated to a temperature of 600 K. Calculate

(A) Moles and pressure of gas in both the containers before heating. (B) Moles and pressure in two containers after heating. Assume that initially the larger container is completely evacuated.

1 ml of gaseous aliphatic compound CnH3nOm is completely burnt in an excess of O2 and cooled to room temperature. The contraction in volume is

A mixture of ethane (C2H6) and ethene (C2H4) occupies 40 litre at 1.00 atm and 400 K , the mixture reacts completely with 130 gm of O2 to produce CO2 and H2O . Assuming ideal gas behaviour , calculate the mole fraction of ethane (C2H6) and ethene (C2H4) in mixture. (R= 0.0821 atm L par mole par kelvin) (IIT 1915)

A mixture of ethane and ethene occupies 35.5 L at 1bar and 405K. The mixture completely reacts with 110 gm of O2 to produce CO2 and H2O. What was the composition of original mixture or what was themoles of ethane and ethene in the mixture (Given R= 0.0821 L atm K^-1mole^-1)

A mixture of ethane and ethene occupies 41L at 1atm and 500K. The mixture completely reacts with 10/3 mole of O2 to produce CO2 and H2O.The mole fractions of ethane and ethene in the mixture are respectively (Given R= 0.0821 L atm K^-1mole^-1)

A solution contains Na 2​ CO 3​ and NaHCO 3​ . 10 mL of the solution required 2.5 mL of 0.1 M H 2​ SO 4​ for neutralisation using phenolphthalein as indicator. Methyl orange is then added when a further 2.5 mL of 0.2 M H 2​ SO 4​ was required. Calculate the amount of Na 2​ CO 3​ and NaHCO 3​ in one litre of the solution.

100mL of a water sample contains 0.81g of calcium bicarbonate and 0.73 of magnesium bicarbonate. The hardness of this water sample expressed in terms of equivalents of CaCO 3​ is:(molar mass of calcium bicarbonate is 162g mol^−1 and magnesium bicarbonate is 146 gmol −1 )

(A) 1000 ppm

(B) 10000 ppm

(C) 100 ppm

(D) 5000 ppm

Solution :

neq​.CaCO3​=neq​Ca(HCO3​)2​+neq​Mg(HCO3​)2​

or 

(W​÷100) ×2 = (0.81​÷ 162)×2 + (0.73÷146)​×2 

∴w=1.0

∴ Hardness=(1.0÷100) ×10^6=10000ppm

Hence correct option is (B) 10000ppm

25 gm of an unknown hydrocarbon upon burning produce 88 gm of CO2 and 9 gm of H2O. this unknown hydrocarbon contains.

(A ) 18g of carbon and 7g of hydrogen

(B) 20g of carbon and 5g of hydrogen

(C) 22g of carbon and 3g of hydrogen

(D) 24 g of carbon and 1g of hydrogen

Solution:

At 300 K and 1atmospheric pressure,10ml of a hydrocarbon required 55 ml of O2 for complete combustion and 40 ml of CO2 is formed. the formula of the hydrocarbon is (JEE MAINS 2019)

(A) C4H8.            (B) C4H7Cl

(C) C4H10           (D) C4H6

A mixture of C 3​ H 8​ (g) & O 2​ having total volume 100 ml in an Eudiometry tube is sparked & it is observed that a contraction of 45 ml is observed what can be the

C3​H8​(g)+5O2​(g)→3CO2​(g)+4H2​O(l)

As par above equation 1 mole of porpane reacts with 5 moles of oxygen to form 3 moles of carbon dioxide.

We know that the number of moles is directly proportional to the volume of the gas.

Thus when 15 ml of propane reacts with 75 ml of oxygen, 45 ml of carbon dioxide will be obtained.

The contraction in the volume will be $15+75-45=45ml$.

This is possible when the composition of the reacting mixture is either 15ml C3​H8​ and 85ml O2​ or 25ml C3​H8​ and 75ml O2​.

Hence, options A and B are the correct answers.

What should be the uncertainty in position if uncertainty in momentum is 1× 10^-2 g cm/sec. and value of h is 6.6252 × 10^-34 joule sec.?

If uncertainty in postion of an electron is same as the ∆x of He atom. If the ∆p of electron is 32×10^5 then find the ∆p in He atom?

what should be the uncertainty inthe the velocity of an electron if the uncertainty in its position is 0.005 nm, the mass of electron is 9.109× 10^-31 kg and the value of h is 6.6252 × 10^-34 jpule /second ?

Why an electron Cannot be present in the nucleus according to the Heisenberg uncertainty principle?

In H atom if the electron moves from nth orbit to 1st orbit by transition in multi steps, then the total number of lines observed in the spectrum are 10, then find out the value of n.

A certain electronic transition from an excited state to Ground state of the Hydrogen atom in one or more steps gives rise to 5 lines in the ultra violet region of the spectrum.How many lines does this transition produce in the Infra red region of the spectrum?

In a hydrogen spectrum if electron moves from 6th to 2nd orbit by transition in multi steps then find out the number of lines in spectrum

In a hydrogen spectrum if electron moves from 7 to 1 orbit by transition in multi steps then find out the total number of lines in the spectrum.

Calculate the ratio of maximum wave length of Lyman & Balmer series ?

The wave number of 1st line of Balmer series of hydrogen spectrum is 15200 cm–1 The wave number of 1st line of Balmer series of Li^+2 spectrum will be ?

Calculate the frequency of the last line of the Lyman series in hydrogen spectrum.

Calculate the wavelength of 3rd line of Brackett series in hydrogen spectrum.

Calculate the wavelength of 1st line of Balmer series in Hydrogen spectrum.

Find out the ratio of the moles of hydrogen and carbon dioxide obtained after 6 successive effusion step initially present in 1:1 molar ratio

Answer Key: 22^6

5.7 g of bleaching powder was suspended in 500 mL of water. 25 mL of this suspension on treatment with KI and HCl liberated iodine which reacted with 24.35 mL of 10N​ Na2​S2​O3​. Calculate the percentage of available chlorine in bleaching powder.

Answer Key: 30.33 %

A metal carbonate on heating is converted to metal oxide and is reduced to 60% of its original weight. The equivalent weight of the metal is

Answer Key: 25

A plant virus is found to consist of uniform cylindrical particle of 150 Angstrom in diameter and 5000 Angstrom long. The specific volume of the virus is 0.75 mL g−1. if the virus is considered to be a single particle, find its molar mass.

Answer key : 7.092×10^7

A sample of ozone gas is found to be 40% dissociated into oxygen. The average molecular mass of sample should be :

The Normality of 4.9% (w/w) H2SO4 solution having density .02 gm/ml is ?

Ans key: (1.02 N )

Calculate the normality of HCl solution whose 500 ml is utillised to neutralise the 1500 ml of N/10 NaOH solution.

And : (3/10)

Henry`s law is not applicable for the aqueous solution of.......

(A) O2 

(B) N2

(C) SO3

(D) He

Answer (C) 

Explanation: Henry`s law is not applicable for the aqueous solution of those gas which undergoes  chemical reactions with solvent (water).

Here SO3 react with water to form sulphuric acid.

Henry`s law constant of CO2 in water at 298K is 5/3 k bar. If pressure of CO2 is 0.01 bar, then find its mole fraction.