When CNG or LPG undergoes complete combustion, the products formed are

• CO₂ and H₂O

• CO₂, SO₂, and H₂O

• CO₂ only

• CO₂, CO, and H₂O

The process of converting sugars into alcohols is known as

• pasteurisation

• sterilisation

• homogenisation

• fermentation

Which one of the following man-made fibers are also called artificial silk?

• Acrylic

• Polyester

• Nylon

• Rayon

The following observations were made by students A, B, C and D when they rubbed solid baking soda on dry litmus paper The correct observation was made by the student

• C

• D

• A

• B

PET bottles and jars are commonly used for storing edible items. PET is a very familiar form of

• rayon

• polyamide

• polyester

• acrylic

When carbon dioxide is passed through clear lime water solution, it turns milky. The milky appearance of lime water is due to

• presence of soluble calcium carbonate

• curdling of milk due to lime in lime water

• presence of impurities in lime water

• presence of insoluble calcium carbonate

37.

In order to determine acidic, basic or neutral character of solutions, a student tabulated the following results after experimentation. Which of the following observations has been tabulated correctly?

Case	Test Solution	Colour change on red litmus paper	Colour change on blue litmus paper	Acidic/Basic/neutral
A	NaCl	No change	Red	Acidic
B	Lime water	Blue	No change	Neutral
C	Vinegar	No change	No change	Neutral
D	Washing soda	Blue	No change	Basic

 

• C

• D

• A

• B

A laboratory thermometer shows five small divisions between the markings of 55°C and 56°C. This means that the thermometer can read correctly up to

• 55.2°C

• 55.25°C

• 55.1°C

• 55.5°C

Bronze is an alloy of

• copper and zinc

• copper and tin

• copper and iron

• copper and aluminium

Match List I with List II and choose the correct answer from the codes given below the lists

List I (Polymer)	List II (Monomer)
A. PAN	(i) Chloroethene
B. Natural rubber	(ii) Caprolactum
C. Nylon-6	(iii) Isoprena
D. PVC	(iv) Acrilonitrile

• A B C D$\to$(iv) (iii) (ii) (i)

• A B C D$\to$(i) (ii) (iii) (iv)

• A  B C  D$\to$(iii) (iv) (i) (ii)

• A B C D$\to$(ii) (i) (iii) (iv) .