InterviewSolution
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InterviewSolution
This section includes InterviewSolutions, each offering curated multiple-choice questions to sharpen your knowledge and support exam preparation. Choose a topic below to get started.
| 51. |
Fish : Bilateral symmetry : : Starfish : ___ |
| Answer» Radial symmetry - Body of fish is Bilaterally symmetrical while body of starfish is Radially symmetrical. | |
| 52. |
Which one of the following depict the correct representation of atomic radius (r) of an atom ? A. (i) and (ii)B. (ii) and (iii)C. (iii) and (iv)D. (i) and (iv). |
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Answer» Correct Answer - B The atomic radius of an element is the distance from the centre of the nucleus of its atom and the last shell which contains electrons. Therefore both (ii) and (iii) represent the correct atomic radius of the element. |
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| 53. |
The positions of three elements `A,B` and `C` in the periodic table are shown here (a) State whether `A` is a metal or non-metal? State whether `C` is more reactive or less reactive than `A` (c) Will `C` be larger or smaller in size than `B`? (d) Which type of ion, cation or anion, will be formed by element `A`? |
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Answer» (a) Element `A` is in group 17. Now, group 17 is one the right side of the periodic table whre non-metals (called halonges) are placed. So, element `A` is non metal. It is a haloven. (b) In group 17 of halogens, the chemical reactivity decreases on going down in a group. Thus, element `C` will be less reactive than element `A`. (c) On going from left to right in a period, the side of atoms decreases. So, the atom of `C` will be smaller in size than an atom of `B`. (d) Element `A` of group 17 has 7 valence electrons. So it will accept 1 electron to form a negatively charged ion `A^(-)`. The negatively charged ionis called an anio. Thus, elements of the periodic table are as follows: |
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| 54. |
An element X (atomic number 17) combines with an element. Y (atomic number 20) to form a compound. (i) Write the positions of these elements in the modern periodic table. (ii) Write the formula of the compound formed. Justify your answer in each case. |
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Answer» (i) The electronic configurations of the two elements are : X (Z = 17) 2, 8, 7 , Y (Z = 20) 2, 8, 8, 2 Element X is present in group 17 (halogen family) since it has 7 valence electrons. Element Y is placed in group 2 (alkaline earth family) since it has 2 valence electrons. (ii) Element Y is a metal with valency 2 while element X is a non-metal with valency 1. Therefore, the two combine to form compound `YX_(2).` |
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| 55. |
Given below are the atomic radii of three elements A, B and C of the peroodic table,each having n electrons in the outermost shell of its atom. Answer the following (i) Will the valencies of these elements be the same or different ? (ii) which the element will have the highes atomic number ? |
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Answer» (i) All the elements have the same number of electrons in the their outermost shell i.e., valence shell. Hence, these elements will be present in the same group of the periodic table and their valencies will be the same. (ii) In a group, atomic radii of elements increase as we move from top to bottom. Hence, using the given data of atomic radii the order radii the order of these elements from top to bottom would be A, B and C. We know that the atomic number of elements increases as we go down a group of the periodic table. Thus, element C will have the highest atomic number. |
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| 56. |
Given below are the atomic radii of some elements of second period. `{:("Element",B,O,N,C,),("Atomic Radius in pm",88,66,74,77,):}` Arrange these elements in the increasing order of their atomic number. Give reason for your answer. |
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Answer» Along a period, the atomic numbers of the elements increase and atomic radii decrease. This means that the two are inversely proportional to each other. Increasing order of atomic numbers : `BltCltNltO.` |
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| 57. |
Element X forms a chloride with the formula `XCl_(2)`, which is a solid with a high melting point. X would most likely be in the same group of the Periodic Table asA. NAB. MgC. AlD. Si |
| Answer» Correct Answer - (b) Mg | |
| 58. |
Animal showing three germ layers |
| Answer» Correct Answer - Triploblastic | |
| 59. |
The animals with three germ layers are called _____A. DiploblasticB. MonoblasticC. TripletD. Triploblastic |
| Answer» Correct Answer - Triploblastic | |
| 60. |
The ______ are exclusively marine.A. MolluscsB. CoelenteratesC. AnnelidsD. Echinoderms |
| Answer» Correct Answer - Echinoderms | |
| 61. |
According to Robert Whittaker, all multicellular animals are included in kingdom …………….. |
| Answer» Correct Answer - Animalia | |
| 62. |
I am a small, fish-like marine animal with notochord present throughout the body length. |
| Answer» Correct Answer - Amphioxus | |
| 63. |
Phylum - Hemichordata |
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Answer» (i) Body of these animals is divided into parts - proboscis, collar and trunk. (ii) Notochord is present in proboscis region only . Hence, they are called as hemichordates . (iii) These animals are also called as acorn worms. (iv) These are marine animals live in burrows in sand . (v) They have one to many pharyngeal gill slits. (vi) They are unisexual or some may be hermaphrodite. e.g. Balanoglossus , Saccoglossus |
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| 64. |
Annelida, Arthropoda, Reptilia, Mollusca. |
| Answer» Reptilia - Others are non-chordates whereas reptitia are chrodates. | |
| 65. |
Which animal is referred to as friend of farmers? |
| Answer» Earthworm is referred to as friend of farmers. | |
| 66. |
Write the characteristics of following animals with reference to their classification: Frog |
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Answer» (i) Frog belongs to class Amphibia. (ii) Can live in water as well as on land during adult life. (iii) Skin is without any exoskeleton and is usually kept moist for respiration. (iv) They have two pairs of appendages. Digits are without claws. (v) External ear is absent but tympanum (external hearing structure) is present. |
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| 67. |
Chordata |
| Answer» The animals which have dorsal, supporting notochord in their bodies are called chordates. | |
| 68. |
What are significant figures? |
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Answer» Significant figures in a measurement are the figure or digits that are known with certainty plus one that is uncertain (i.e. Last digit ). Or, Significant figures in a measured value of the physical quantity tell the number of digit in which we have confidence. Example :- 1984 has 4 significant figures |
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| 69. |
What is the basic difference in the electronic configuration of the elements belonging to group 1 and group 2 ? |
| Answer» All elements belonging to group 1 have one electron in the valence shell while all elements belonging to group 2 have two electrons in their valence shell. | |
| 70. |
Give the name and electronic configuration of second alkali metal. |
| Answer» The second alkali metal is sodium (Na). Its electronic configuration is 2, 8, 1. | |
| 71. |
What is the similarity in the electronic configuration of Mg, Ca and Sr ? |
| Answer» All the elements belong to group 2 and have two electrons in their valence shell. | |
| 72. |
1. Education is no longer restricted to bookish knowledge and the four walls of the classrooms. Apart from the activities in the classrooms, laboratories and libraries, a student has an opportunity to find out and express his or her hidden potential in the form of various extra-curricular activities. Youth festivals are the best platform for such activities. 2. It is essential for the all-round development of a student. There are many extra-curricular activities such as declamation, debate, painting, music dance, singing, recitation and so on. 3. Mere classroom studies make it boring and monotonous. Students need some outlets for their energies. They need opportunities for entertainment also. When students prepare for various activities, they have a sense of achievement, a sense of doing something useful. Preparing the stage for the show, receiving the guests or the participants from the other institutions and looking after them inculcate in them a sense of responsibility, co-operation and tolerance. 4. As the competitions of the youth festivals are organized among the students of almost the same age, they get rid of stage phobia. They no longer feel shy to face the audience too and learn to face them. Thus they cultivate self-confidence. 5. Youth festivals are the best means to search the talent among the youth. These budding artists will become the singers, actors and orators of tomorrow. Youth festivals prove to be the stepping stones for the students’ future life. Absence of youth festivals makes a student’s life insipid and boring. As such, students take to subversive activities. If they remain busy in preparing for competitions in youth festivals, their time is used in a productive and fruitful way. Choose the most appropriate options:- (Any Five) a) Students should take part in extra-curricular activities for i) scoring extra marks, ii) an all -round development , iii) for adding extra spice to academic life, iv) both ii and iii b) Youth festivals inculcate in the students i)a sense of responsibility , ii a sense of importance, iii) a sense of cooperation and tolerance, iv) both i and iii c) Absence of youth festivals makes a student’s life i)full of activities, ii) full of fun, iii) insipid and boring, iv) overburdened d) Youth festivals help the students to get rid of the i)Mathematics phobia, ii) stage phobia , iii) shyness to face the audience, iv) both ii and iii e) Which word in the passage is an antonym of ‘tasteful’ i)boring, ii) subversive, iii) insipid, iv) budding f) Youth festivals are the i)Building blocks of the students’ future life, ii) stepping stones of the students’ future life, iii) guiding force of the students’ future life, iv) all of these |
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Answer» My free fire uid 1293986343 |
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| 73. |
The tendency to gain electron _____ on going from top to bottom in a group of the periodic table. |
| Answer» Correct Answer - decreases | |
| 74. |
What type of oxide would Eka-aluminium form ?A. `EO_(3)`B. `E_(3)O_(2)`C. `E_(2)O_(3)`D. `EO` |
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Answer» Correct Answer - C It is the correct answer. |
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| 75. |
Scolidon : Cartilagenous : : Pomfret : ______ |
| Answer» Bony - The exoskeleton of Scolidon is Cartilagenous whereas that of Pomfret is bony. | |
| 76. |
Phylum-Echinodermata (Echino-spiny, derma-skin) |
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Answer» (i) Calcareous spines are present on the body of these animals, hence, are called as Echinoderms. (ii) These animals are found only in ocean. (iii) Their body is triploblastic, eucoelornate. It is radially symmetrical in adult stage. However, shows bilateral symmetry in larval stage. (iv) They perform locomotion with the help of tube feet. Tube feet are also useful to catch the prey. Some animals are sedentary. (v) They have skeleton made up of calcareous spines and /or ossicles (plates). (vi) These animals are unisexual. (vii) These animals have good ability of regeneration .e.g. Starfish, Brittle star, Sea-urchin, Sea cucumber, etc. |
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| 77. |
Cartilagenous fish |
| Answer» Correct Answer - Shark | |
| 78. |
Phylum - Arthropoda |
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Answer» (i) These animals have jointed appendages. Hence, they are called as Arthropods. (ii) The planet Earth has highest number of animals from this phylum. Hence, these are the largest successful animals in the kingdom animalia. (iii) These animals are found in all types of habitat ranging from deepest oceans to highest mountains. (iv) Body of these animals is triploblastic,eucoelomate, bilaterally symmetrical and segmented. (v) Chitinous exoskeleton is present around their body. (vi) These animals are unisexual. e.g. Crab, spider, scorpion, millipede, cockroach, centipede, butterfly, honey bee, etc. |
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| 79. |
Hemichordates are also called …………. |
| Answer» Correct Answer - acorn worms | |
| 80. |
A connecting link between Non-chordates and chordates. |
| Answer» Correct Answer - Balanoglossus | |
| 81. |
Through the point of view of evolution,…………... is considered as connecting link between non-chordates and chordates. |
| Answer» Correct Answer - Balanoglossus | |
| 82. |
Locomotory organs in Annelids |
| Answer» Setae, Suckers, Parapodia | |
| 83. |
How are animals classified broadly? |
| Answer» Animals are broadly classified into Chordates and Non-chordates. | |
| 84. |
Phylum Aschelrninthes (Nemalhelminthes) |
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Answer» (i) The body of these animals is long thread-like or cylindrical. Hence, called as round worms. (ii) They are either free living or endoparasites. Free living are either aquatic or terrestrial. (iii) These animals are triploblastic and pseudocoelomate. (iv) Body is unsegmented and covered with cuticle. (v) These animals are unisexual, i.e. sexes are separate. e.g. Ascaris, (Intestinal worm), Filarial worm, LoaIon, (Eye worm) |
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| 85. |
Animal whose body is made up of segments |
| Answer» Correct Answer - Earthworm | |
| 86. |
In urochordata, notochord is present th roughout the body length. |
| Answer» False. In urochordata, notochord is present in Oily tail region. | |
| 87. |
Give the characteristics of the following with examples : Class Reptilia |
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Answer» (i) According to evolution of animals, these are the first true terrestrial animals with creeping movement. (ii) They creep on land as their body cannot be lifted up. (iii) They are cold blooded (Poikilotherrns) animals. (iv) The skin is dry and scaly. (v) External ear is absent. (vi) They are oviparous. (vii) Digits are provided with claws. e.g. lizard, crocodile, tortoise, snake, etc. |
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| 88. |
Animal having tentacles around mouth. |
| Answer» Correct Answer - Hydra | |
| 89. |
Spicules are made up of …………… |
| Answer» calcium carbonate | |
| 90. |
Pseudopodia, Cilia, Setae, Ostia. |
| Answer» Ostia - Others are locomotory organs whereas ostia are pores on the body of porifera. | |
| 91. |
Animals belonging to Porifera have special types of cells called ……………... |
| Answer» Correct Answer - collar cells | |
| 92. |
Cnidoblast bearing tentacles are present around the mouth in Porifera. |
| Answer» False. Cnidoblast bearing tentacles are present around the mouth in Coelenterata. | |
| 93. |
Amoeba: Pseudopodia : : Earthworm : _____ |
| Answer» Setae - Amoeba uses Pseudopodia for locomotion while Earthworm uses Setae for locomotion. | |
| 94. |
Why do you think the noble gases are placed in a separate group? |
| Answer» Noble gases are inert elements. Their properties are different from the all other elements. Therefore, the noble gases are placed in a separate group. | |
| 95. |
What were the criteria used by Mendeléev in creating his Periodic Table? |
| Answer» Mendeleev used atomic masses of the elements as the criteria for creating his periodic table. In this table, the elements were arranged in order of increasing atomic masses. | |
| 96. |
Besides gallium, which other elements have since been discovered that were left by Mendeléev in his Periodic Table? (any two) |
| Answer» Two other elements are scandium (Sc) and germanium (Ge). In their gaps, the elements with names Eka-boron and Eka-silicon were placed. | |
| 97. |
Rohan and Vikram are very good friends. Rohan studies in class 9 whreas Vikram studies in class 10. During a dental check up in the school, Rohan was told that tooth decay had just started on the top of his large back teeth and where one tooth touches another. He also heard the dentist telling his assistant that pH change is the cause of tooth decay. Rohan could not understand anything. He told everythig to Vikram. Vikram could understanding what had happened. He explained everything to Rohan and also gave him advice to prevent further tooth deay. (a) What is meant by tooth decay? (b) What type of micro-organisms are responsible for causing tooth decay? (c) How does tooth decay start? (d) What is meant by saying that pH change is the cause of tooth decay? (e) What advice do you thim Vikram gave to Rohan to prevent further tooth decay? (f) What values are displayed by Vikram in this episode? |
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Answer» (a) Tooth decay is the gradual destruction of the hard, outer tissues of the tooth (such as enamel and dentine) leading to the formation of cavities or caries in the tooth. In most simple terms, tooth decay means rotting of tooth. Progressive tooth decay can lead to the death of tooth. (b) Bacteria (which are present in the mouth). (c) When we eat food (including surgary food), some of the food particles stick to our teeth and accumulate on the surface of our teeth. The bacteria present in our mouth brak down the sugar present in these food particles to form acid. This acid first attackes the enamel (and then dentine) of our tooth and corrodes it. This starts the tooth decay. (d) The acid formed by the action of bacteria on the surgary food present on out teeth lowers the pH in mouth (making it more acidic). Tooth decay starts when the pH of acid formed in the month falls below 5.5. This is because then the acid becomes strong enough to attack the hard enamel of our teeth and corrode it gradually. This is why it is sid that pH change in the mouth is the cause of tooth decay. (e) Vikram gave the following advice to Rohan to prevent further tooth decay: (i) Clean the mouth throughly after eating food by rising with lots of clean water so as to remove the food particles sticking on the surface of teeth. (ii) Clean the teeth by brushing by using a toothpase (at least twice a day). The toothpaste is basic in nature. The baisc toothpaste neutralises the excess acid in the mouth and prevents tooth decay. (iii) Eat less of sugary foods like sweets, toffees, chocolates ice cream and candy, etc. (f) The values displayed by Vikeram are (i) Awareness of the cause of tooth decay (ii) Knowledge that toothpaste is basic in nature which can prevent tooth decay, and (iii) Concern for the dental health of his friend. |
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| 98. |
The position of three elements A,B and C in the periodic table are shown below- |
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Answer» (a) In group 12 of periodic table B is metal and In group 17 A and C is nonmetal and halogens. (b) A is more reactive than C because, We take A as Cl and C as Iodine.Now,
(c) B is larger than A in periodic table because,
(d) A and C ( A and C belongs to halide family ) mainly more occurs as anion and B (belongs to Zn family) occurs as both in given condition because,
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| 99. |
Give reason as to why the atomic radii of elements increase in a group while moving from top to bottom ? |
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Answer» The atomic radii of elements increase in a group while moving from top to bottom because a new shell is being added when we go down a group. This increases the distance between the outermost electrons and the nucleus so as to increase the atomic size in spite of increase in nuclear charge. |
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| 100. |
The first person to perform classification of animals was ____A. TheophrastusB. LinnaeusC. AristotleD. Meyer |
| Answer» Correct Answer - Aristotle | |