Question 2 : <img style='object-fit:contain' src='https://teachmint.storage.googleapis.com/question_assets/cbse_ncert/61b19d2c273b230584979bb4.JPG' />
In the given figure, name the compound.
Question 3 :
What are the two properties of carbon which lead to the huge number of carbon compounds we see around us?
Question 4 :
Give a test that can be used to differentiate between saturated and unsaturated hydrocarbons.
Question 5 :
Why is the conversion of ethanol to ethanoic acid an oxidation reaction?
Question 7 :
What is the term given to mixing of water and acid/base compound
Question 11 :
The following reaction is an example of :
$Fe_{2}O_{3} + 2Al \rightarrow Al_{2}O_{3} + 2Fe$
Question 12 :
Write the balanced chemical equations for the following reactions:
Barium chloride + Potassium sulphate $\rightarrow$ Barium sulphate + Potassium chloride
Question 13 :
Write the balanced chemical equations for the following reactions:
Zinc+ Silver nitrate $\rightarrow$ Zinc nitrate + Silver
Question 14 :
Which of the statements about the reaction below are incorrect?
2PbO(s) + C(s) $\rightarrow$ 2Pb(s) + $CO_{2}(g)$
(i) Lead is getting reduced
(ii) Carbon dioxide is getting oxidised
(iii) Carbon is getting oxidised
(iv) Lead oxide is getting reduced
Question 15 :
Balance the following chemical equations:
$BaCl_{2} + H_{2}SO_{4} \rightarrow BaSO_{4} + HCl$
Question 17 :
Anaemia is the consequence of a deficiency of haemoglobin in our body. State TRUE or FALSE?
Question 21 :
Which of the following properties of a proton can change while it moves freely in a magnetic field?
Question 23 :
At the time of short circuit, the current in the circuit
Question 24 :
State TRUE or FALSE. An electric generator works on the principle of electromagnetic induction.
Question 25 :
Which of the following property of a proton can change while it moves freely in a Magnetic Field?
Question 26 :
The number of pair(s) of sex chromosomes in the zygote of humans is
Question 27 :
The theory of evolution of species by natural selection was given by
Question 29 :
If a trait 'A' exists in 10% of the population ofan asexually reproducing species and a trait 'B' exists in 60% of the same population, which trait is likely to have arisen earlier?
Question 32 :
An element reacts with conductivity of metals oxygen to give a compound with a high melting point. This compound is also soluble in water. The element is likely to be
Question 34 :
Which one of the following metals is the most reactive and stored in kerosene?
Question 35 :
Which of the following methods is suitable for preventing an iron frying pan from rusting?
Question 37 :
The potential difference between the terminals of an electric heater is 60 V when it draws a current of 4 A from the source. What current will the heater draw if the potential difference is increased to 120 V?
Question 38 : <img style='object-fit:contain' src='https://teachmint.storage.googleapis.com/question_assets/cbse_ncert/61b19d3d273b230584979bc8.jpg' /> In the above diagram, the resistors $R_{1},R_{2},R_{3}$ have the values 5 Ω, 10 Ω, 30 Ω, respectively, which have been connected to a battery of 12 V. Calculate the total current in the cicruit.
Question 39 :
How many number of electrons constitute 1 coulomb of charge ?
Question 40 :
What are the factors resistance of conductor does not depend upon?
Question 41 :
Use Mendeleev's periodic table to predict the formulae for the oxides of the elements 'K'.
Question 42 :
By considering their position in the periodic table, which one of the following elements would you expect to have maximum metallic characteristic?: Ga, Ge, As, Se and Br
Question 43 :
Name three elements that have a single electron in their outermost shells.
Question 44 :
Name three elements that have a single electron in their outermost shells.
Question 45 :
Use Mendeleev's periodic table to predict the formulae for the oxides of the elements 'C'.
Question 48 :
Asolar water heater cannot be used to get hot water on:
Question 50 :
There is infinite storage of fossil fuel inside the earth. TRUE or FALSE ?
Question 51 : <img style='object-fit:contain' src='https://teachmint.storage.googleapis.com/question_assets/cbse_ncert/61b19c8a273b230584979afa.JPG' />
In the above diagram, equal volumes of hydrochloric acid and sodium hydroxide solutions of same concentration are mixed and the pH of the resulting solution is checked with a pH paper. What would be the colour obtained? Refer the above scale for answering.
Question 52 :
Fill in the blank: Calcium nitrate ($Ca(NO_3)_2$) is formed using $Ca(OH)_2$(base) and _______(acid)
Question 53 :
What will be the action of the Soap solution on litmus paper?
Question 54 :
Name the acid present in ant sting and give its chemical formula.
Question 56 : <img style='object-fit:contain' src='https://teachmint.storage.googleapis.com/question_assets/cbse_ncert/61b19cb9273b230584979b30.JPG' />
In the above diagram of a compound, which all functional groups are present:
Question 57 : <img style='object-fit:contain' src='https://teachmint.storage.googleapis.com/question_assets/cbse_ncert/61b19cb3273b230584979b29.JPG' />
Write the name of the above compound.
Question 58 : <img style='object-fit:contain' src='https://teachmint.storage.googleapis.com/question_assets/cbse_ncert/61b19cbf273b230584979b37.JPG' />
Name the reaction involved for the above reacting compounds.
Question 61 :
Balance the chemical equation:- $BaCl_2 + H_2SO_4 → BaSO_4 + HCl$.
Question 64 :
What is the substance getting oxidised in $4Na(s) + O_2(g) → 2Na_2O(s)$ ?
Question 65 :
Why are oil and fat containing food items are flushed with nitrogen?
Question 68 :
Complete the following statment : Brain is enclosed in a hard shell know as __________ .
Question 71 :
State whether the statement is TRUE or FALSE : Reproduction is linked to stability of population of a species.
Question 72 :
What would be the ratio of chromosome number between an egg and its zygote?
Question 73 :
Why does bread mould grow profusely on a moist slice of bread rather than on a dry slice of bread?
Question 74 :
Can you consider cell division as a type of reproduction in unicellular organism?
Question 75 : <img style='object-fit:contain' src='https://teachmint.storage.googleapis.com/question_assets/cbse_ncert/61cc185078c526e972caea1d.PNG' />
In the above figure, would a Planaria cut vertically into two halves regenerate into two individuals?
Question 76 : <img style='object-fit:contain' src='https://teachmint.storage.googleapis.com/question_assets/cbse_ncert/61b19ced273b230584979b6c.PNG' />
<img style='object-fit:contain' src='https://teachmint.storage.googleapis.com/question_assets/cbse_ncert/61cc185478c526e972caea2a.PNG' />
In the above images, the first image is the ray of light incident on a concave mirror and the second image is the complete path of the ray. Is the second image correct depiction of the path?
Question 78 :
Under which of the following conditions a concave mirror can form an image larger than the actual object?
Question 79 :
Complete this law of refraction: Incident ray, refracted ray and normal at the point of incidence lie _____________ .
Question 80 :
What type of image will form by a concave mirror, when an object is placed a little beyond centre of curvature of the mirror.
Question 81 :
State TRUE or FALSE. Electric motors are used in electric fans, refrigerators, mixers, etc.
Question 82 :
An electric oven of 2 kW power rating is operated in a domestic electric circuit (220V) that has a current rating of 5 A. Will the fuse blow off?
Question 83 :
Why does a compass needle get deflected when brought near a bar magnet?
Question 84 : <img style='object-fit:contain' src='61b19cf2273b230584979b72' />
In the above arrangement if the key is taken out (the circuit is made open) and magnetic field lines are drawn over the horizontal plane ABCD, the lines are
Question 86 :
Pick the right combination of terms which has no fossil fuel.
Question 87 :
Given below are a few statements related to biodiversity. Pick those that correctly describe the concept of biodiversity -
(i) Biodiversity refers to the different species of flora and fauna present in an area
(ii) Biodiversity refers to only the flora of a given area
(iii) Biodiversity is greater in a forest
(iv)Biodiversity refers to the total number of Individuals of a particular species living in an area
Question 88 :
The pH range most conducive for life of fresh water plants and animals is
Question 90 :
The most rapidly dwindling natural resource in the world is -
Question 91 :
Alloys are homogenous mixtures of a metal with a metal or non-metal. Which among the following alloys contain non-metal as one of its constituents?
Question 92 :
When a metal X is treated with cold water, it gives a basic salt Y with a molecular formula XOH (Molecular mass = 40) and liberates a gas Z which easily catches fire. Identify X
Question 93 :
During extraction of metals, electrolytic refining is used to obtain pure metals. In this electrolytic cell, while refining silver metal, where do we get pure silver after passing electric current?
Question 94 :
Give the formula of the stable binary compounds that would be formed by the combination of following pairs of element.
Al and $Cl_2$
Question 95 :
Compound X and aluminium are used to join railway tracks. The reaction taking place is called 'Thermite reaction'. Is this statement TRUE or FALSE?
Question 98 :
If a grass hopper is eaten by a frog, then the energy transfer will be from
Question 99 :
Excessive exposure of humans to U V-rays results in
(i) damage to immune system
(ii) damage to lungs
(iii) skin cancer
(iv) peptic ulcers
Question 101 :
The image of a candle flame formed by a lens is obtained on a screen placed on the other side of the lens. If the image is three times the size of the flame and the distance between lens and image is 80 cm, what is the nature of the image ?
Question 102 :
Identify the type of reaction Limestone is heated strongly to form quicklime and carbondioxide gas is evolved
Question 103 :
Three 60 W incandescent bulbs are connected in a parallel. Calculate the total power consumed.
Question 104 :
In human beings, the statistical probability of getting either a male or female child is 50 : 50. The sex of an infant is determined by the type of sex chromosome contributed by the male gamete. State TRUE or FALSE.
Question 105 :
State TRUE or FALSE. New species may be formed if chromosome number changes in the gamete
Question 106 :
The three elements A, B and C with similar properties have atomic masses X, Y and Z respectively. The mass of Y is approximately equal to the average mass of X and Z. What is such an arrangement of elements called as?
Question 109 :
An element X of group 15 exists as diatomic molecule and combines with hydrogen at 773 K in presence of the catalyst to form a compound, ammonia which has a characteristic pungent smell. How many valence electron does the element X have?
Question 110 :
Which of the following gives the correct increasing order of the atomic radii of O, F and N ?
Question 111 : <img style='object-fit:contain' src='61b19d15273b230584979b99' />
In the above figure, The path of a ray of light passing through a rectangular glass slab tested by four students are shown in above Figure as A, B, C and D. Which one of them is correct?
Question 113 :
Atomic number of a element is 10. Identify the period to which this element belongs?
Question 114 : <img style='object-fit:contain' src='61b19d19273b230584979b9e' />
In the above figure, three 2 Ω resistors, A, B, and C, are connected. Each of them dissipates and can stand a maximum power of 18 W without melting.What is the maximum current that can flow through the A resistors.
Question 115 :
A metal carbonate X on reacting with an acid gives a gas which when passed through a solution Y gives the carbonate back. On the other hand, a gas G that is obtained at anode during electrolysis of brine is passed on dry Y, it gives a compound Z, used for disinfecting drinking water. What is the name of the compound G .
Question 117 :
A person is advised to wear spectacles with convex lens. What defect of eye is he suffering from?
Question 118 :
A person with a myopic eye cannot see objects beyond 1.2 m distinctly. What should be the type of corrective lens used to restore proper vision?
Question 120 : <img style='object-fit:contain' src='61b19d75273b230584979c09' />
In the above image a prism ABC (with BC as base) is shown in different orientations. A noarrow beam of white light is incident on the prism. In which of these cases the third colour from the top resembels the colour of the sky?
Question 122 :
Roots, stems and leaves of some plants develop into new plants through :-
Question 123 :
Advantage of vegetative propagation is that all plants produced are genetically similar enough to the parent plant to have all its characteristics. Is it TRUE or FALSE?
Question 125 :
The rate of general body growth begins to slow down, reproductive tissues begin to mature. Is it TRUE or FALSE?
Question 127 :
To obtain an erect image of an object, using a concave mirror of focal length 15 cm. What should be the range of distance of the object from the mirror?
Question 128 :
A concave lens has focal length of 15 cm. At what distance should the object from the lens be placed so that it forms an image at 10 cm from the lens?
Question 129 :
What would be the size of image formed by concave mirror when the object is placed between centre of curvature and focus?
Question 130 :
The ray of light which is perpendicular to the reflecting surface is called ___.
Question 133 :
Silver ornaments become black after few days of wearing them due to the formation of ____.
Question 134 : <img style='object-fit:contain' src='61b19d4c273b230584979bd9' />
From the above image, answer the following: Pratyush took sulphur powder on a spatula and heated it. He collected the gas evolved by inverting a test tube over it, as shown in figure above. What will be the action of gas on dry litmus paper?
Question 136 :
A coil of many circular turns of insulated copper wire wrapped closely in the shape of a cylinder is called a ____.
Question 137 :
A coil of insulated copper wire is connected to a galvanometer. What will happen if a bar magnet is withdrawn from inside the coil ?
Question 139 :
The region surrounding a magnet, in which the force of the magnet can be detected, is said to have a -
Question 141 :
Element X forms a chloride with the formula $XCl_2$, which is solid with a high melting point. X would most likely to be in the same group of the periodic table as
Question 144 :
Which element has two shells, both of which are completely filled with electrons ?
Question 146 :
The rise of sea-water during high tide is caused by the gravitational pull of the:
Question 147 :
Which of the following gases is the main constituent of natural gas?
Question 149 :
In order to make efficient solar cooker, the cover of cooker box should be made of:
Question 151 :
How can you as an individual contribute or make a difference to the management of water resources?
Question 153 :
Water harvesting is an age-old concept in India. Name the ancient water harvesting structures found in India.
Question 154 :
Exploitation of forests by the local people can be prevented by
Question 156 :
Carbon and its compounds are used as fuels because they burn in air releasing a large amount of heat energy. TRUE or FALSE?
Question 157 : <img style='object-fit:contain' src='61b19d62273b230584979bf3' />
In the above figure, which compound electron dot structure is given?
Question 158 :
While cooking, if the bottom of the vessel is getting blackened on the outside, it means that:
Question 161 :
Which of the following are the reasons for adopting contraceptive methods?
Question 164 :
Reason(s) why more complex organisms cannot give rise to new individual through regeneration is/are ?
Question 165 :
What are the changes seen in girls at the time of puberty?
Question 166 :
The angle of actual position and apparent position of a star are _______ when the star is present directly above our head.
Question 168 :
State TRUE or FALSE : We see a rainbow in the sky only after rainfall because the water droplets behave like prisms and disperse sunlight.
Question 169 :
A prism ABC (with BC as base) is placed in different orientations. A narrow beam of white light is incident on the prism as shown in the figures. In which of the following cases , after dispersion, the third colour from the top corresponds to the colour of the sky?
Question 170 :
What is the thin membrane through which light enters the eye?
Question 171 :
Find the focal length of a convex mirror whose radius of curvature is 32 cm.
Question 172 :
Where should an object be placed in front of a convex lens to get a real image of the size of the object?
Question 173 :
A doctor has prescribed a corrective lens of power + 1.5 D. Find the focal length of the lens.
Question 174 :
Find the power of a concave lens of focal length 2 m.
Question 175 :
A doctor has prescribed a corrective lens of power + 1.5 D. Is the prescribed lens diverging or converging?
Question 177 :
Give an example of a metal which is a liquid at room temperature.
Question 178 :
Food cans are coated with tin and not with zinc because
Question 179 :
An element reacts with oxygen and give slaked lime. The element is
