CHEMISTRY SSC- I
SECTION — A (Marks 12)
Time allowed: 20 Minutes
NOTE:- Section-A is compulsory. All parts of this section are to be answered on the question paper itself. It should be completed in the first 20 minutes and handed over to the Centre Superintendent Deleting/overwriting is not allowed. Do not use lead pencil. SECTION — A (Marks 12)
Q. 1 Circle the correct option i.e. A/B/C/ D. Each part carries one mark.
The number of moles in 54 gm of water will be:
A. 2 B. 2.5 C. 3 D. 4
Carbon has _________isotopes.
A. 2 B. 1 C. 3 D. 4
Which one is correct electronic configuration according to Auf Bau Principle?
A. 1S2, 2S2, 2P6,3S4 B. IS2,2S2,2P4,3S2.3P4
C. 1S2,2P6,3S2,3P4 D. 1S2,2S22P6, 3S2,3P2,
The electron affinity increases from left to right along a period. due to:
A. Decrease in nuclear charge B. Decrease in atomic radius
C. Increase in atomic size D. increase in shielding effect
NaCI forms colorless cubic crystal. Which of the following has also the same cubic crystal as NaCI crystal?
CsCI B. CaCl2 C. MgO D. MgCl2
Which substance is NOT covalent?
A. H2O B. HCN C. CaO D. CO2
‘V ∝ T’ Relationship represents:
A. Boyle’s law B. Charle’s law C. Avogadro’s law D. General gas equation
Which one of the following substances is not sublimate?
A. Iodine B. Ammonium chloride C. Sodium chloride D. Benzoic Acid
A solution of NaOH contains 30 gms of this compound in 1.5 dm3 of solution. What is the Molarity of this solution?
A. 0.2 M B. 1 M C. 0.75 M D. 0.5 M
Oxidation state/number of ‘Cr’ in K2Cr207 is:
A. -14 B. -6 C. +6 D. +2
In chrome plating, the compound used as electrolyte is:
A. Only H2S04 B. Cr2(SO4)3 C. Cr2(SO4)3 and some drops of HCI D. Cr203
Al203 is an example of oxide.
A. Strongly acidic B. Basic C. Weakly Acidic D. Amphoteric
CHEMISTRY SSC – I
Time allowed: 2:40 Hours Total Marks Sections B and C: 43
NOTE: – Answer any nine parts from Section ‘B’ and any two questions from Section ‘C’ on the separately provided answer book. Use supplementary answer sheet i.e. Sheet-B if required. Write your answers neatly and legibly. (Graph paper may be provided)
SECTION — B (Marks 33)
Q. 2 Answer any ELEVEN parts. The answer to each part should not exceed 3 to 4 lines. ( 11 x 3 = 33 )
Define Biochemistry, Element and Molecular ion.
Calculate the mass of 3.24 x1018 atoms of iron. (M. Mass of Iron=56).
Write electronic configuration, group number and period number of the following:
Write names of Blocks of Periodic Table, also write names of Halogen group elements.
Shielding effect increases from top to bottom along a group and remains the same along a period. Why?
Why do group VIII A elements have very less number of compounds? Give reasons.
Write any four types of bonds and define any one of them.
Write any three properties of Ionic compounds.
Give reasons for the following. a. Why are gases highly compressible?
Why do gases have relatively low densities under normal conditions?
Give reasons: a. Why do solids have relatively higher densities?
Why do Ionic compounds have higher melting points than Molecular solids?
Fill in the missing spaces:
Solute Solvent State of resulting Solution Examples
gas Solid Solid –
solid – – Carbon particles in air
Calculate the new molarity when 100cm3 of water is added to I00cm3 of 0.5M HCl.
Identify Reducing agents from the following:
a. Fe203 + 3C0 →2Fe+ 3C02 b. WO3 + 3H2 → W + 3H20
Define Electroplating. Also write conditions for good electroplating.
What are Noble metals? Give four examples.
SECTION — C (Marks 20)
Note: Attempt any TWO questions. All questions carry equal marks. (2 x 10 = 20)
Q. 3 a. Define Molecular Mass. Calculate. Molecular masses of C10H8 and (NH2)2C0 (03)
b. Oxygen is converted into Ozone (03) during thunderstorms. Calculate the mass of (03) Ozone if 7.25 moles of Ozone are formed in a storm. (03)
c. Describe the presence of sub-shells in shells. (04)
Q. 4 a. Describe method of recovering metals from their ores with examples. (06)
b. Write any four properties of Metals. (04)
Q. 5 a. Write a note on “Solutions of Solids”. (06)
b. What is Zinc Plating? Write complete Process of Zinc Plating. (04)