SOME BASIC CONCEPTS OF CHEMISTRY Quiz-27

Some basic concepts of chemistry Quiz-27

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IIT JEE exam which consists of JEE Main and JEE Advanced is one of the most important entrance exams for engineering aspirants. The exam is held for candidates who are aspiring to pursue a career in the field of engineering and technical studies. Chemistry is important because everything you do is chemistry! Even your body is made of chemicals. Chemical reactions occur when you breathe, eat, or just sit there reading. All matter is made of chemicals, so the importance of chemistry is that it's the study of everything..

Q1.1 g of a sample of NaOH was dissolved in 50 mL of 0.33 M alkaline solution of KMnO_4 and refluxed till all the cyanide was converted into OCN^⊖. The reaction mixture was cooled and its 5 mL portion was acidified by adding H_2 SO_4 in excess and then titrated to end point against 19.0 mL of 0.1 M FeSO_4 solution. The percentage purity of NaCN sample is

•  55.95 %
•  65.95 %
•  75.95 %
•  85.95 %

Solution

Q2.1 mole of SO_2 Cl_2 is dissolved in water and Ca(OH)_2 is added to neutralise acidic solution Moles of Ca(OH)_2 required are

•  2
•  3
•  4
•  5

Solution

Q3. If equal volumes of 1 M KMnO_4 and 1 M K_2 Cr_2 O_7 solutions are used to oxidise Fe^(2+)in acidic medium, then Fe^(2+) will be oxidised

•  More by K_2 Cr_2 O_7
•  More by KMnO_4
•  Equal in both the cases
•  The data is insufficient to predict the answer

Solution

Q4. Urea solution is one molal. Urea present in 1 kg solution is

•  60 g
•  56.6 g
•  10.60 g
•  10.0 g

Solution

Q5. What volume of 0.2 M KOH will be required to neutralize 100 mL of 0.1 M H_3 PO_4 using methyl red indicator (change of colour pink → yellow) and then bromothymol blue indicator is added

•  50 mL
•  100 mL
•  150 mL
•  200 mL

Solution
 

Q6. When a soluble lead compound is added to a solution containing orange K_2 Cr_2 O_7 solution

•  PbCr_2 O_7 is precipitated
•  PbCrO_4 is precipitated
• PbCrO_3 is precipitated
•  None of the above is precipitated

Solution

Q7. Number of atoms in 20 g Ca is equal to number of atoms in

•  20 g Mg
•  1.6 g CH_4
•  1.8 g H_2 O
•  1.7 g NH_3

Solution

Q8. If each O-atom has two equivalents, volume of one equivalent of O_2 gas at STP is

•  22.4 L
•  11.2 L
•  5.6 L
•  44.8 L

Solution

Q9. The density of ammonia at 30℃ and 5 atm pressure is

•  3.42 g L^(-1)
•  2.42 g L^(-1)
•  1.71 g L^(-1)
•  3.84 g L^(-1)

Solution

Q10. 50 mL of H_2 SO_4 require 10 g CaCO_3 for complete decomposition H_2 SO_4 is

•  9.8%
•  4.9%
•  19.6%
• 2.45%

Solution