-
question_answer1)
Three candles X, Y, and Z are fixed on a table. A glass chimney is placed over candle X, and is rested on wooden blocks in a manner which allows the entrance of oxygen. To candle Y, a glass chimney is placed in such a way that it is simply rested on the table. For candle Z, a similar arrangement is made along with the placement of a glass plate over the chimney. Candle _____i____ bums freely. The flame of candle _____ii_____ will flicker off giving smoke, and that of candle _____iii_____ will simply go off.
The information in which alternative completes the given statements?
A)
i-X, ii-Y, iii-Z done
clear
B)
i-Z, ii-Y, iii-X done
clear
C)
i-Y, ii-X, iii-Z done
clear
D)
i-Z, ii-X, iii-Y done
clear
View Solution play_arrow
-
question_answer2)
Which of the following tables correctly represents the substance with the type of combustion?
A)
B)
C)
D)
View Solution play_arrow
-
question_answer3)
The ignition temperature of sodium is very _____i____. To prevent its _____ii_______ combustion, it is stored under _______iii______,. The information in which alternative completes the given statements?
A)
i-low, ii-rapid, iii-Kerosene done
clear
B)
i-low, ii-spontaneous, iii-Kerosene done
clear
C)
i-high, ii-rapid, iii- water done
clear
D)
i-high, ii-spantaneous, iii-water done
clear
View Solution play_arrow
-
question_answer4)
The gas that is used in fire extinguishers is
A)
Nitrogen done
clear
B)
Hydrogen done
clear
C)
Sulphur dioxide done
clear
D)
Carbon dioxide done
clear
View Solution play_arrow
-
question_answer5)
Radhika took some sodium bicarbonate in a conical flask and set up the apparatus as shown in the given diagram. She added cone. sulphuric acid into the conical flask using a funnel.
Which of the flowing statements is correct for the given experiment?
A)
The gas coming out of the delivery tube is heavier than air and will make the candle glow brightly. done
clear
B)
The gas coming out of the delivery tube is lighter than air and will extinguish the candle. done
clear
C)
The gas coming out of the delivery tube is heavier than air and will extinguish the candle. done
clear
D)
The gas coming out of the delivery tube is lighter than air and will make the candle glow brightly. done
clear
View Solution play_arrow
-
question_answer6)
Which of the following tables correctly matches the given zones of a candle flame with their respective characteristics?
A)
B)
C)
D)
View Solution play_arrow
-
question_answer7)
Ordinarily, kerosene oil bums in air with a yellow flame. However, in stoves, it bums with a blue flame. Which of the following statements explains the above observation?
A)
Complete combustion of kerosene takes place in stoves. done
clear
B)
The ignition temperature of kerosene is attained easily in stoves. done
clear
C)
Stoves are made of iron and kerosene bums with a blue flame in the presence of iron. done
clear
View Solution play_arrow
-
question_answer8)
Consider the given diagram X and Y in the given figure represent
A)
Sulphur oxides and nitrogen oxides done
clear
B)
Silicon oxides and nitrogen oxides done
clear
C)
Sulphur oxides and chlorine gas done
clear
D)
Silicon oxides and chlorine gas done
clear
View Solution play_arrow
-
question_answer9)
Incomplete combustion of fossil fuels releases a gas 'X?. This gas is poisonous in nature and it bums with a blue flame. Which gas does X represent?
A)
Ozone done
clear
B)
Chlorine done
clear
C)
Carbon dioxide done
clear
D)
Carbon monoxide done
clear
View Solution play_arrow
-
question_answer10)
Harish performed two different experiments I and II. In experiment I, he provides a substance 'X? with some heat. He found out that a sudden reaction takes place to form heat, light, and sound. In experiment II, he provides heat to a substance 'Y?. He found out that when Y bums, only heat and light are produced. Experiment I represents an example of __i__, and experiment II represents an example of __ii___. The information in which alternative completes the given statement?
A)
i-Explosion, ii-Rapid combustion done
clear
B)
i-Explosion, ii-Sportaneous combustion done
clear
C)
i-Spontaneous combustion, ii-Explosion done
clear
D)
i-Rapid combustion, ii-Spontaneous combustion done
clear
View Solution play_arrow
-
question_answer11)
Sakshi took a piece of four substances W, X, Y, and Z. She tried to bum each of them by bringing a lighted matchstick near them. She observed that Y and Z bum readily, whereas W bums readily only after sustained heating. However, X does not bum at all. Among the given substances taken by Sakshi, which substance has the highest ignition temperature?
A)
W done
clear
B)
X done
clear
C)
Y done
clear
D)
Z done
clear
View Solution play_arrow
-
question_answer12)
Swati took two glass plates I and II. She introduced them to the-different zones of a flame (as shown in the figure). She held them there with a pair of tongs for about 10 seconds. She observes that a circular-blackish ring has developed on plate I, while no such blackish ring is observed on plate II. From Swati's experiment, it can be concluded that ______i______ zone is the zone containing unburnt particles, and the ___ii___ zone is the zone of complete combustion.
The information in which alternative completes the given statement?
A)
i-outermost, ii-Innermost done
clear
B)
i-Innermost, ii-Outermost done
clear
C)
i-Innermost, ii-Middle. done
clear
D)
i-Middle, ii-Innermost done
clear
View Solution play_arrow
-
question_answer13)
Rajesh made two paper cups I and II by folding a sheet of paper. He pours 50 mL water in cup II, and heats both cups separately with the help of a candle (as shown in the figure). Rajesh observes that while one paper cup burns readily, the other does not burn. He observed that paper cup ____i____ does not burn since its ignition temperature was ______ii______ while heating.
The information in which alternative completes the given statement?
A)
i-I, ii-reached done
clear
B)
i-II, ii-reached done
clear
C)
i-I, ii-not reached done
clear
D)
i-I, ii-not reached done
clear
View Solution play_arrow
-
question_answer14)
Geeta took four combustible substances I, II, II, and IV. She found out that the ignition temperatures of I, n, III, and IV is\[{{233}^{o}}C\], \[{{473}^{o}}C,\] \[{{210}^{o}}C,\]and \[{{170}^{o}}C,\] respectively. She heats all the substances to \[{{190}^{o}}C,\]. Among the given substances, which substance will catch fire when heat is supplied to it?
A)
I done
clear
B)
II done
clear
C)
III done
clear
D)
IV done
clear
View Solution play_arrow
-
question_answer15)
If a goldsmith wants to make jewellery of gold and silver, then he has to melt them. To do this, he will use the ___i____ zone of the flame as this zone is the ____ii____ zone of the flame. The information in which alternative completes the given statement?
A)
i-Innermost, ii-Hottest done
clear
B)
i-Innermost, ii-Moderately hot done
clear
C)
i-Outermost, ii-Moderately hot done
clear
D)
i-Outermost, ii-Hottest done
clear
View Solution play_arrow
-
question_answer16)
A certain gas is used by living organisms for respiration, and this is used in the process of combustion. In the process of combustion, the gas reacts with combustible substances to produce heat. The mentioned gas is
A)
Oxygen done
clear
B)
Nitrogen done
clear
C)
Carbon dioxide done
clear
D)
Carbon monoxide done
clear
View Solution play_arrow
-
question_answer17)
Sujit was performing an experiment in the laboratory. He collected four substances I, II, III, and IV and kept all of them in contact with air at room temperature. He observed that substance III suddenly bursts into flames. Then, he heated I, II, and IV and found out that while I and II catch fire, substance IV does not. However, substance IV catches fire on prolonged heating. Which substance undergoes spontaneous combustion in Sujit's experiment?
A)
I done
clear
B)
II done
clear
C)
III done
clear
D)
IV done
clear
View Solution play_arrow
-
question_answer18)
Ravi takes three substances X, Y, and Z. On heating these substances he observes that they bum at different temperatures. He finds out that X catches fire on little heating, while Y and Z do not catch fire. On further heating of Y and Z, he observes that Y catches fire, while Z does not. The correct arrangement of X, Y, and Z in order of their increasing ignition temperatures is
A)
\[X<Y<Z\] done
clear
B)
\[Z<Y<X\] done
clear
C)
\[Z<X<Y\] done
clear
D)
\[Y<X<Z\] done
clear
View Solution play_arrow
-
question_answer19)
Why is it never advised to sleep in a room with burning coal fire?
A)
Incomplete combustion of coal produces carbon monoxide, which is poisonous done
clear
B)
Incomplete combustion of coal produces carbon dioxide, which is poisonous done
clear
C)
Burning of coal produces oxides of nitrogen, the fumes of which are very toxic done
clear
D)
Burning of coal produces oxides of nitrogen that combine with moisture present in air to form acids done
clear
View Solution play_arrow
-
question_answer20)
Global warming is a result of ____i_____ percentage of ____ii_____ in air. The information in which alternative completes the given statement?
A)
i-An increased, ii-Carbon dioxide done
clear
B)
i-A decreased, ii-Carbon dioxide done
clear
C)
i-An increased, ii-nitrogen done
clear
D)
i-A decreased, ii-nitrogen done
clear
View Solution play_arrow