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Q1. Which one of the following can be used to confirm whether drinking water contains a gamma emitting isotope or not?

microscope

lead plate

spectrophotometer

scintillation counter

Q2. Which one of the following is a mixed fertilizer?

Urea

CAM

Ammonium Sulphate

NPK

Q3. The chemical used as a 'fixer' in photography is

sodium sulphate

sodium thiosulphate

Ammonium persulphate

Borax

Q4. "The final Agent Orange raid in Vietnam took place in 1970: .... Areas have begun to bloom again. But 19 years after the war's end, it seems plain that Agent Orange is killing and maiming human beings, something it never intended to do. The apparent toxic fallout from those clouds....is a crop of human miseries including cancers, miscarriages and birth defects -- that may persist for decades." -- The offensive substance referred to in this quotation is .....

DDT used as an insecticide

a complex mixture of herbicides and weedicides used to increase agricultural output in the then South Vietnam under the US aid programme

A complex mixture of DDT and other insecticides used as aerial sprays for protection against malaria and other tropical diseases

Dioxin used as defoliants.

Q5. Which radioactive pollutant has drawn the attention of the public, due to its occurrence in the building material?

Plutonium

Thorium

Radon

Radium

Q6. Which one of the following is in the correct sequential order in which these appeared under stimulated primitive earth condition?

Methane, Hydrogen cyanide, nitriles, aminoacids

Hydrogen cyanide, methane, nitriles, aminoacids

Aminoacids, nitriles, Hydrogen cyanide, methane

Nitriles, aminoacids, methane, Hydrogen cyanide

Q7. If a gas is compressed to half of its original volume at 27°C to what temperature should it be heated to make it occupt its original volume?

327°

600°C

54°C

300°C

Q8. The main constituents of pearl are .....

calcium carbonate and magnesium carbonate

Aragonite and conchiolin

ammonium sulphate and sodium carbonate

calcium oxide and ammonium chloride

Q9. Monozite is an ore .....

Zirconium

Thorium

Titanium

Iron

Q10. Galvanised iron sheets are protected from rusting due to the presence of a layer of ....

lead

chromium

Zinc Oxide

tin

Q11. Water is a good solvent of ionic salts because

it has a high boiling point

it has a high dipole moment

it has a high specific heat

it has no colour

Q12. Which one of the following chemicals is responsible for the depletion of ozone layer in the atmosphere?

Chlorofluorocarbons

Nitrous Oxide

Sulphur dioxide

Carbon dioxide

Q13. In which type of rocks are metals like gold and copper mostly found?

Old igneous

Old metamorphic

Old sedimentary

New metamorphic

Q14. Gypsum is added to cement clinker to

increase the tensile strength of the cement

bind the particles of calcium silicate

decrease the rate of setting of cement

facilitate the formation of colloidal gel

Q15. Of the following, which one is ana element?

Ruby

Sapphire

Emerald

Diamond

Q16. Elements having atomic number higher than '92' in the periodic table are known as .....

Transitional elements

Rare earth elements

Transuranic elements

Alakaline earth metals

Q17. Which of the following metals is extracted from the Monazite sand found in plenty in India?

Gold

Uranium

Thorium

Copper

Q18. Soap was never actually discovered but instead gradually evolved from crude mixtures of alkaline and fatty material. Up to 1800, soap was believed to be a mechanical mixture of fat and alkali, then Chereul, a French chemist showed that soap formation, was actually a achemical reaction. Which one of the following follows from the above statement?

Soap is a natural product, whose existence was later established

Alkaline and fatty material, both being natural material, their mixture which is used as soap is still natural materials mixture

Chevreul discovered the process of soap making

Crude mixing of alkaline and fatty material in early days was actually chemical process of formation of soap.

Q19. Water which contains soluble salts of calcium and magnesium is known as

heavy water

soft water

mineral water

hard water

Q20. Paraffin is a by-product of ...

petroleum refining

processing of agricultural wastes

cottage industries involving bee-keeping

leather industry

Q21. Assertion (A): Activated charcoal is used for decolourising sugar solution. Reason {R}: Activated charcoal absorbs the impurities on its surface.

Both A and R are individually true and R is the correct explanation of A

Both A and R are individually true but R is not the correct explanation of A

A is true but R is false

A is false but R is true

Q22. Sparkling red colour after the blast of fire crackers is due to the presence of .....

Magnesium

Sodium

Sulphur

Strontium

Q23. The highest grade of coal, whose surface is hining and has the highest calorific value is

lignite

peat

bituminous

anthracite

Q24. Which of the following chemicals in automobile exhaust can cause cancer?

carbon monoxide

Polycyclic hydrocarbons

Lead tetroxide

oxides of nitrogen

Q25. Match the following organic acids (in alphabets) with their sources (in numbers) : (A) Lactic Acid (B) Acetic Acid {C} Citric Acid (D) Butyric Acid ..... (1) Lemon (2) Rancid Butter (3) Milk (4) Vinegar (5) Wine

A5, B4, C3, D2

A3, B1, C4, D5

A2, B5, C1, D3

A3, B4, C1, D2

Q26. The drugs -- caffeine, tannin and nicotine are

steroids

cortisones

alkaloids

mild alkalis

Q27. Oridinary dry air consists of the following: (1) Nitrogen (2) Oxygen (3) Argon (4) Carbon dioxide. What is the decreasing sequence of these in percentage?

1,2,3 and 4

1,2,4 and 3

2,1,3 and 4

2,1, 4 and 3

Q28. Which one of the following is a non-metallic mineral?

Manganese

Magnesium

Gypsum

Bauxite

Q29. Assertion (A): A dry cell cannot be recharged. Reason {R}: The chemical reaction in a dry cell is reversible.

Both A and R are individually true and R is the correct explanation of A

Both A and R are individually true but R is not the correct explanation of A

A is true but R is false

A is false but R is true

Q30. Assertion (A): Detergents can easily remove oil and dirt from soiled garments. Reason {R} : Detergents increase the surface tension of water.

Both A and R are individually true and R is the correct explanation of A

Both A and R are individually true but R is not the correct explanation of A

A is true but R is false

A is false but R is true

Q31. Assertion (A): Red phosphorous is preferred to white phosphorous in the manufacture of matches. Reason {R}: Red phosphorous is non-poisonous in nature.

Both A and R are individually true and R is the correct explanation of A

Both A and R are individually true but R is not the correct explanation of A

A is true but R is false

A is false but R is true

Q32. Why DDT has been banned in western countries?

it remains in environment for a long time

the insects are immunised

it is a highly poisonous insecticide

none of the above

Q33. Main constituents of Biogas are ....

Methane and Carbon dioxide

Ethylene and Carbon dioxide

Butane and Carbon monoxide

Methane and Carbon monoxide

Q34. Urea is prepared by the chemical reaction of .....

Ammonium Sulphate and calcium chloride

Acetamid and ethyl alcohol

chlorine and water

Ammonia and Carbon dioxide

Q35. Which of the following fertilisers leaves acidic residue?

Ammonium phosphate

Sulphate of potash

Ammonium sulphate

Urea

Q36. Assertion (A): Alkalies are used for washing utensils. Reason {R}: Alkalies are readily soluble in water.

Both A and R are individually true and R is the correct explanation of A

Both A and R are individually true but R is not the correct explanation of A

A is true but R is false

A is false but R is true

Q37. Match the following Ores (in alphabets) with the metals derived from them (in numbers): (A) Argentite (B) Bauxite (C} Haematite (D) Cuprite ..... (1) Copper (2) Iron (3) Aluminium (4) Silver

A4, B3, C2, D1

A1, B4, C3, D2

A2, B1, C4, D3

A1, B2, C3, D4

Q38. Match the following products (in alphabets) and the chemicals used for their manufacture (in numbers): (A) Glass (B) Match {C} Fertiliser (D) Salt ..... (1) Phosphorus (2) Sodium Chloride (3) Sodium Silicate (4) Potassium Sulphate

A3, B4, C2, D1

A3, B1, C4, D2

A2, B3, C1, D4

A4, B3, C2, D1

Q39. Match the following ores (in alphabets) with the metals derived from them (in numbers): (A) Bauxite (B) Monazite (C} Malachite (D) Pitchblende ..... (1) Copper (2) Uranium (3) Thorium (4) Aluminium

A3, B4, C2, D1

A3, B1, C2, D4

A4, B3, C1, D2

A4, B3, C2, D1

Q40. Chlorine is ...

a rare earth element

a halogen

a noble gas

coinage metal

Q41. Which of the following is an insecticide?

TNT

DDT

Salicylic acid

Ammonium phosphate

Q42. The common ore of aluminium is ....

Bauxite

Chromite

Cryolite

Monazite

Q43. The substance generally used in the tip of safety match stick is

Red Phospohorus

Sodium

Yellow Phosphorus

Antimony trisulphide

Q44. The process by which metal surface is coated with thin layer of zinc is called ...

vulcanizing

galvanising

electroplating

none of these

Q45. Which of the following is useful in the chemistry of photography?

Silver Bromide

Aluminium Hydroxide

Sodium Chloride

Potassium nitrate

Q46. Gasohol is mixture of gasoline and ...

Ethyl Alcohol

Methyl alcohol

Kerosene

Butyl alcohol

Q47. Which of the following is commonly present in the acids?

oxygen

sulphur

nitrogen

hydrogen

Q48. "Dry Ice" is ........

solid carbon di oxide

ice dust

liquefied nitrogen

liquefied hydrogen

Q49. Isotopes of the same element differs in the number of

Protons

Neutrons

Electrons

Positrons

Q50. Stainless steel contains which of the following?

Aluminium and Zinc

Chromium and Carbon

Zinc and Mercury

Copper and Cadmium

Answers Evaluate

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