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In the following questions, two statements are given, one is Assertion (A) and the other is Reason (R). Examine the statements carefully and mark the correct answer according to the instructions given below:

A: In the equation NH3 + HCl → NH4Cl, Gay-Lussac’s law is not applicable to NH4Cl. R: NH4Cl is not a gas. A. If both A and R are... View Article

In the following questions, two statements are given, one is Assertion (A) and the other is Reason (R). Examine the statements carefully and mark the correct answer according to the instructions given below:

A: 1 Gram molecule of sulphur also represents 1 gram atom of sulphur. R: Atomic city of sulphur is one. A. If both A and R are correct and R... View Article

In the following questions, two statements are given, one is Assertion (A) and the other is Reason (R). Examine the statements carefully and mark the correct answer according to the instructions given below:

A: Normality of 0.1 M H2SO4 is 0.2 N R: H2SO4 is a dibasic acid A. If both A and R are correct and R is the correct explanation of A B. If... View Article

Which of the following pairs of substances illustrates the law of multiple proportions?

A. CO and CO2 B. NaCl and NaBr C. H2O and D2O D. MgO and Mg(OH)2 Solution: (A) As per the law of multiple proportions, when two... View Article

Two containers P and Q of equal volume (1 litre each) contain 6 g of O₂ and SO₂ respectively at 300 K and 1 atmosphere, then;

A. Number of molecules in P is less than that in Q B. Number of molecules in P and Q is same C. Number of molecules in Q is less than that... View Article

Find the electric charge in couloumb of 9.0 gm of Al³⁺ ions.

A. 9.6 × 104 B. 6.9 × 104 C. 2.9 × 105 D. 4.80 × 10-19 Solution: (A) No of moles of Al3+ = 9 / 27 = 0.33 No.... View Article

An ore contains 1.24% of the mineral argentite Ag₂S by mass. How many grams of this ore would have to be processed in order to obtain 1.0 g of pure solid silver?

A. 23.15 g B. 69.45 g C. 92.6 g D. 46.3 g Solution: (C) Consider the mass of ore = x gm Molecular weight of Ag2S = 248g = (Mass of... View Article

0.32g of metal on treatment with an acid gives 112mL of hydrogen at NTP. Calculate the equivalent weight of the metal.

A. 58 B. 32 C. 11.2 D. 24 Solution: (B) Given, Mass of metal = 0.32 g Volume of hydrogen = 112ml = 112 × 10−3 L Now... View Article

What is the total number of atoms of elements present in a mole of ammonium dichromate?

A. 19 B. 6.023 x 1023 C. 114.47 x 1023 D. 84 x 1023 Solution: (C) So, 1 molecule of ammonium dichromate, (NH4)2 Cr2O7 will have 19... View Article

Which of the following has the highest normality?

A. 1M H2SO4 B. 1M H3PO3 C. 1M H3PO4 D. 1M HNO3 Solution: (A) Normality = Molarity × nfactor Since all have the same molarity.... View Article

Calculate the molarity of a solution obtained by mixing 50 mL of 0.5 M H₂SO₄ and 75 mL of 0.25 M H₂SO₄.

A. 0.375 M B. 0.35 M C. 0.045 M D. 0.45 M Solution: () No.of moles of 0.05 L H2SO4 = 0.5 x 0.05 = 0.025 No.of moles of 0.075 L H2SO4... View Article

The atomic weights of two elements X and Y are 20 and 40 respectively. If ‘a’ gm of X contains ‘b’ atoms, how many atoms are present in ‘2a’ gm of Y?

A. b B. a C. 2 b D. (2 a/b) Solution: (A) No of moles of X = a / 20 No. of atoms of X = a / 20 × N = b (given) = a = 20b / N... View Article

Which of the following represents the formula of a compound which contains 26% nitrogen and 74% oxygen?

A. N2O B. NO C. NO2 D. N2O5 Solution: (D) Given, % Nitrogen in the compound = 26%, % Oxygen in the compound = 74%, So, mass of... View Article

Which of the following chemical equations is incorrectly balanced?

A. Sb2S3 + 12HCl→ 2H3SbCl6 + 3H2S B. 3IBr + 4NH3 → NI3 + 3NH4Br C. 2KrF2 + 2H20 → 2Kr + 202 + 4HF D. PCl3 + 3H20 →... View Article

If the atomic mass of carbon were set at 50 amu, what would be the value of Avogadro’s number?

A. 5.01 × 1024 B. 6.022 × 1024 C. 1.66 × 1024 D. None of these Solution: (D) Given, Atomic mass of C = 50 amu... View Article

Aadhaar and Other Laws (Amendment) Act, 2019

Mr Ravi Shankar Prasad, Minister of Electronics and Information Technology, introduced the Aadhaar and Other Laws (Amendment) Bill 2019 in the... View Article

Choose the proper option after studying the following statement (T = True, F = False)

1. The percent composition of vinyl chloride and its polymer PVC are the same. 2. The percent composition of phosphorus trioxide (P2O3 )is... View Article

The density of Al metal is 2.7 g cm^-3. An irregularly shaped piece of aluminum weighing 40.0 g is added to a 100 mL graduated cylinder containing 50.0 mL of water. upto what height the water level will rise in the cylinder?

A. 14.8 mL B. 79.6 mL C. 64.8 mL D. 50 mL Solution: (C) d = m / v Now, V = m / d = 40 / 2.7 = 14.8 cm3 The water level in the... View Article

The unit J Pa^-1 is equivalent to;

A. m3 B. cm3 C. dm3 D. None of these Solution: (A) J / Pa = Work / Pressure = Nm / Nm-2 = m3... View Article

Haemoglobin present in blood contains 3.72% by mass iron. Calculate the number of iron atoms In 2.0 g of haemoglobin.

A. 4.53 × 1026 B. 4.53 × 1024 C. 5.95 × 1019 D. 8 × 1020 Solution: (D) Mass % of iron in haemoglobin = 3.72 %... View Article