Maharashtra HSC Board or 12th Chemistry Important Question 2019
(1) Select and write the most appropriate answer from the given alternatives for each sub-question:
(1) Schottky defects are observed in which solid among the following?
(b) Cesium Chloride
(c) Zinc sulphide
(d) Stainless steel
(2) No machine has an efficiency unity, is stated in-
(a) First law of thermodynamics
(b) Second law of thermodynamics
(c) Third law of thermodynamics
(d) Hess law of constant heat summation
(3) Potential of saturated calomel electrode is-
(a) 0.242 V
(b) 1.1 V
(c) 0.337 V
(d) 0.28 V
(4) Which of the following compounds is used as a semi permeable membrane?
(a) Potassium ferrocyanide
(b) Potassium argent cyanide
(c) Sodium meta aluminate
(d) Copper ferrocyanide
(5) Which among the following minerals does NOT contain aluminum?
(c) China clay
(6) The group 15 element having inner electronic configuration as of argon is –
(a) (Phosphorous (z = 15)
(b) Antimony (z = 51)
(c) Arsenic (z = 33)
(d) Nitrogen (z = 7)
(2). Answer any ‘SIX’ of the following;
(1) Write chemical reactions involved in Van Arkel method for refining Titanium.
(2) Explain the relationship between Gibb’s standard energy change of the reaction and equilibrium constant.
(3) A face centred cube (FCC) consists of how many atoms? Explain.
(4) Describe isolation method in determination of rate law and order of reaction.
(5) Explain the following methods to protect metals from corrosion:
(6) Write the Nernst equation and explain the terms involved.
(7) What happens when dilute sulphuric acid is treated with (a) Fe (b) CaF2?
(8) Define (a) Osmosis (b) Freezing point.
(3). Answer any One of the following:
(1) State third law of thermodynamics. Write applications of standard molar entropy. Draw neat labeled diagram of electrolytic refining of blister copper.
Determine the density of Cesium chloride which crystallizes in BBC type structure with the length 412.1 pm. The atomic masses of Cs and C1 are 133 and 35.5 respectively.
Predict the co-ordination No. of Cs ion if rcs+ = 1.69A and rcs– = 1.81A.
(4). Select and write the most appropriate answer from the given alternatives for each sub-question:
(1) Sodium acetate reacts with Ethanoyl chloride to form
(a) Acetic acid
(c) Acetic anhydride
(d) Sodium formate
(2) Natalite is a mixture of
(a) Diethyl ether and methanol
(b) diethyl ether and ethanol
(c) Diethyl ether and methanol
(d) Dimethyl ether and ethanol
(3) Maltose is a
(4) Which one of the following oxidation state of Manganese is unstable?
(a) + 2
(b) + 4
(c) + 5
(d) + 7
(5) Answer any THREE of the following:
(1) What is the action of following reagents on glucose?
(a) Bromine water
(b) Dilute HNO3
(c) Hydroxyl amine
(2) Define ligand. Write four postulates of Werner’s theory.
(3) Write reactions involved in preparation of potassium dichromate from chrome iron ore.
(4) What is matamerism?
Write the structure and IUPAC name of ‘methyl-n-propyl ether’.
What is the action of hot HI on it?
(6) Answer any ONE of the following:
(1) (a) How are the following polymers prepared?
(b) Classify the following drugs into Anagesics and Antibiotics-
(2) How are the following conversions carried out?
(1) 2-methylbution-1-01 into 2-methylbutanoic acid.
(2) Phenylethene into Benzoic acid
(3) Benzoic acid into metanitrobenzoic acid.
What the action of Benzene Sulphonyl Chloride on primary, secondary and tertiary amines?
Write two uses of formaldehyde.