Carbon and its Compound
I.
(i) Which of the following statement is true regarding the electronegativity of atoms in water molecule?
(a) Hydrogen is more electronegative than oxygen
(b) Hydrogen is less electronegative than oxygen
(c) Electronegativity is same in Hydrogen and oxygen
(d) Hydrogen and oxygen do no show significant electronegativity in water
(ii) What is the shape of water molecule?
(a) Linear (b) Trigonal planar (c) Bent (d) Octahedral
(iii) Select the correct type of bonding in a water molecule
(a) Ionic Bonding (b) Covalent Bonding (c) Hydrogen Bonding (d) None of these
(iv) The correct electron dot structure of a water molecule is
(v) The H—O—H bond angle in water molecule is
(a) 109.5° (b) 180° (c) 90° (d) 105.0°
Periodic Classification of Elements
I. Around the year 1800, only 30 elements were known. Dobereiner in 1817 and Newlands in 1866 tried to arrange the then known elements and framed laws which were rejected by the scientists. Even after the rejection of the proposed laws, many scientists continued to search for a pattern that correlated the properties of elements with their atomic masses.
The main credit for classifying elements goes to Mendeleev for his most important contribution to the early development of a Periodic table of elements wherein he arranged the elements on the basis of their fundamental property, the atomic mass and also on the similarity of chemical properties. The formulae of their hydrides and oxides were treated as basic criteria for the classification of the elements. However, Mendeleev’s classification also had some limitations as it could not assign the position to isotopes. He also left some gaps in the periodic table.
(i) According to Mendeleev’s Periodic Law properties of elements are periodic function of
(a) atomic mass (b) atomic number (c) number of protons (d) number of electrons
(ii) Why did Mendeleev leave some gaps in the Periodic table?
(a) For elements to be discovered (b) For isotopes (c) For isobars (d) None of these
(iii) If the letter ‘R’ was used to represent any of the elements in the group, then the hydride and oxide of carbon would respectively be represented as
(a) RH4, RO (b) RH4, RO2 (c) RH2, RO2 (d) RH2, RO
(iv) Isotopes are:
(a) Atoms of an element with similar chemical properties but different atomic masses.
(b) Atoms of different elements with similar chemical properties but different atomic masses.
(c) Atoms of an element with different chemical properties but same atomic masses.
(d) Atoms of different elements with different chemical properties but same atomic masses.
(v) How many groups and periods are there in Mandeleev’s periodic table?
(a) 6 group, 8 period (b) 18 group, 7 period (c) 7 group, 18 period (d) 8 group, 6 period
II. Modern periodic table has 18 vertical columns known as groups and 7 horizontal rows known as periods. First period contains 2 elements second and third period contain 8 elements. 4th and 5th period contains 18 elements and 6th and 7th period contains 32 elements. The graph is plotted between atomic number and atomic radius of group 17 and group 1 elements.
(i) Which group elements will have largest atomic size?
(a) Group 1 (b) Group 2 (c) Group 3 (d) Group 18
(ii) Which group elements will gain electrons to form negative ions?
(a) Group 1 (b) Group 2 (c) Group 17 (d) Group 18
(iii) Which element in group 17 has smallest size?
(a) Flourine (b) Bromine (c) Chlorine (d) Iodine
(iv) What happens to atomic radii in a group from top to bottom?
(a) Increases (b) Decreases (c) First decreases then increases (d) Number of shells remains the same
(v) Atomic size decreases from left to right in a period because
(a) Effective nuclear charge increases
(b) Number of shells remains the same
(c) Force of attraction between the nucleus and valence electrons increases (d) All of these
III.
(i) Which element has highest electronegativity?
(a) C (b) N (c) O (d) F
(ii) How electronegativity varies in a period?
(a) Increases from left to right (b) Decreases from left to right (c) First increases then decreases (d) Vary independently
(iii) How electronegativity varies in a period?
(a) Increases down the group (b) Decreasing down the group (c) First increases then decreases down the group (d) Vary independently
(iv) Which of the following has least electronegativity?
(a) Li, (b) Be, (c) O, (d) N
(v) What happens to tendency to gain electron in a period?
(a) Increases, (b) Decreases, (c) Remaining same, (d) First increases then decreases.
How do Organism Reproduce?
I. The male reproductive system consist of portions which produce the germ-cells and other portions that deliver the germ-cells to the site of fertilisation. Testes are located outside the abdominal cavity in scrotum because sperm formation requires a lower temperature than normal body temperature. It also has a role of secretion of male sex hormone which brings changes in appearance seen in boys at the time of puberty. Vas deferens unites wih a tube coming from urinary bladder. Urethra is a common passage for sperms and urine. Prostate gland and seminal vesicles add their secretions so that sperms are now in fluid.
(i) Name the sex hormone associated with males.
(a) Testosterone (b) Progesterone (c) Oestrogen (d) None of these
(ii) Which of the following statements is incorrect?
(a) Sperms are present in a fluid (b) Fluid provides nutrition to sperms
(c) Fluid makes easier transportation of sperms (d) Fluid helps to bind the sperms together
(iii) Testes are located outside the abdominal cavity in scrotum because
(a) sperms formation requires higher temperature than body temperature
(b) sperms formation requires lower temperature than body temperature
(c) it is easier to transport sperms from the scrotum
(d) None of these
(iv) Which of the following statement is incorrect?
(a) Sperms and urine has a common passage from urethra.
(b) Sperms have long tail that helps them to move forward.
(c) Sperms contain genetic material.
(d) Sperms formation requires 1–3°C higher temperature than normal body temperature.
(v) What is the nature of semen?
(a) slightly acidic (b) Neutral (c) Slightly basic (d) Strongly basic
II. Study the table related to sex ratio of females/1000 males in different states and answer the questions that follow:
(i) Name the state which has males to female ratio to maximum extent in 2013-15.
(a) Haryana (b) Kerala (c) West Bengal (d) Uttar Pradesh
(ii) What is major cause of less females than males in India?
(a) Male Foeticide (b) Female Foeticide (c) Natural (d) None of these
Which test is responsible for female foeticide?
(a) UV-Spectroscopy (b) Ultrasound (c) MRI (d) X-Ray
(iv) Which state of India has lowest sex ratio in 2013-15?
(a) Punjab (b) Odisha (c) Haryana (d) Delhi
(v) Which of the following state improves sex ratio in 2013-15 from 2012-14?
(a) Delhi (b) Karnataka (c) Bihar (d) Kerala
Heredity and Evolution
1. In some animals, the temperature at which fertilised eggs are kept determines whether the animal developing in the egg will be male or female. In other animals, such as snails, individuals can change sex, that is sex is not genetically determined. In human beings, sex of individuals is largely genetically determined. All chromosomes in human beings are not paired. We have 22 pairs and one pair of sex chromosomes which is odd and not always a perfect pair.
(i) Which pair of chromosomes are present in Male
(a) XX (b) YY (c) XY (d) XXY
(ii) Which pair of chromosomes are present in female?
(a) XX (b) YY (c) XY (d) XXY
(iii) Who is responsible for birth of male child?
(a) Father (b) Mother (c) Father only in first pregnancy. (d) Mother only in first pregnancy
(iv) How many pairs of chromosomes are called autosomes?
(a) 23 (b) 22 (c) 21 (d) 20
(v) Which of the following statement is true?
(a) Men have short sized X chromosome
(b) Men have one long sized Y chromosome
(c) Men have normal sized Y chromosome
(d) Men have one short sized Y chromosome
Electricity
1. Ohm’s law gives the relationship between current flowing through a conductor with potential difference across it provided the physical conditions and temperature remains constant. The electric current flowing in a circuit can be measured by an ammeter.
Potential difference is measured by voltmeter connected in parallel to the battery or cell. Resistances can reduce current in the circuit. A variable resistor or rheostat is used to vary the current in the circuit.
(i) What type of conductor is represented by the following graph?
(a) Non-ohmic conductor like thermistor (b) Non-ohmic conductor like metal filament
(c) Ohmic conductor like copper (d) None of these
(ii) What type of conductors are represented by the following graph?
(a) Non-ohmic conductor like thermistor (b) Non-ohmic conductor like metal filament
(c) Ohmic conductor like copper (d) None of these
(iii) Which type of conductor is represented by the graph given alongside?
(a) Non-ohmic conductor like thermistor (b) Non-ohmic conductor like metal filament
(c) Ohmic conductor like copper (d) None of these
(iv) What is the slope of graph in (i) equal to?
(a) V (b) I (c) R (d) VI
(v) Which of the following is the factor on which resistance of a conductor does not depend?
(a) Length (b) Area (c) Temperature (d) Pressure
2. Study this table related to material and their resistivity and answer the questions that follow.
(i) What is the range of resistivity in metals, good conductors of electricity?
(a) 10–8 to 10–6 Ωm (b) 10–6 to 10–4 Ωm (c) 1010 to 1014 Ωm (d) 1012 to 1014 Ωm
(ii) Which property of the alloy makes it useful in heating devices like electric iron, toasters, immersion rods, etc.
(a) Higher resistivity (b) Do not oxidise at low temperature
(c) Do not reduce at high temperature (d) Oxidise at high temperature
(iii) Which of the following is used in transmission wires?
(a) Cr (b) Al (c) Zn (d) Fe
(iv) Which is the best conducting metal?
(a) Cu (b) Ag (c) Au (d) Hg
(v) Which of the following is used as a filament in electric bulbs?
(a) Nichrome (b) Tungsten (c) Manganese (d) Silver
Magnetic Effects of Current
1. Study this table related to wattage of home appliances and answer the questions that follow.
(i) Which of the following home appliance is not based on magnetic effect of current?
(a) Ceiling fan (b) Blender (c) Geyser (d) Washing Machine
(ii) Which of the following lighting device is best to use in terms of power consumption?
(a) Bulb (b) CFL (c) Tube light (d) LED
(iii) Which of the following will to consume least power?
(a) Laptop (b) Desktop (c) Printer (d) Blender
(iv) Which of the following will consume maximum power?
(a) Fridge (b) Iron (c) Air conditioner (d) Coffee maker
(v) Many appliance works on the principle of electromagnetic induction. The role which depicts the direction of induced current is as
(a) Faraday’s rule (b) Henery’s rule (c) Fleming’s rule (d) Maxwell’s rule
2. A magnetic stripe card, also referred to as a swipe card or magstripe, is a plastic card with a magnetic strip attached on its surface. This stripe is made of tiny iron-based components whose magnetism can be modified and can therefore be used to store information. A magstripe is quite similar to a magnetic recording tape, which you might find in videotape or a music cassette. The magnetic strip on a card can be ‘written’ or encoded with information because the tiny iron-based particles that make up the strip can be magnetised in different directions by a device that produces a strong magnetic field. This device is a ‘solenoid’, which is basically a coil wound into a tightly packed helix. The wire is wound around a highpermeable, metallic core that produces a strong magnetic field when a current is passed through it. This device encodes the required information onto the stripe, which is then pasted on a plastic card. When a card with a magnetic strip is moved back and forth over the ‘reader head’ , a voltage is induced in the coils of the card reader device. A card reader consists of solenoid too – the same component that is used to write information in the magnetic strip.
This voltage can be amplified and recorded electronically, which is finally read by a computer (or a processor installed within the reader) to authenticate a user (in the case of identity cards) or a transaction (in the case of credit/debit cards).
(i) Which of the following are the devices that uses magnetic theory to record data
(a) The hotel key cards (b) Audio tapes (c) CD’s (d) All of the above
(ii) Name the scientist who gave the principle of electromagnetic field
(a) Oersted (b) Faraday (c) Bohr (d) Ampere
(iii) The force on a wire inside a magnetic field increase when
(a) The current is increased (b) Strength of magnetic field increases (c) Length of wire is increased (d) All of above
(iv) The information of users which are read by the ATM machines are stored on
(a) Magnetic box on card (b) Magnetic strip on card (c) Inside ATM machine (d) None of above
(v) The factors on which one magnetic field strength produced by current carrying solenoids depends are
(a) Magnitude of current (b) Number of turns (c) Heat produced (d) Both (a) and (b)
3. A solenoid is a long helical coil of wire through which a current is run in order to create a magnetic field. The magnetic field of the solenoid is the superposition of the fields due to the current through each coil. It is nearly uniform inside the solenoid and close to zero outside and is similar to the field of a bar magnet having a north pole at one end and a south pole at the other depending upon the direction of current flow. The magnetic field produced in the solenoid is dependent on a few factors such as, the current in the coil, number of turns per unit length etc.
The following graph is obtained by a researcher while doing an experiment to see the variation of the magnetic field with respect to the current in the solenoid. The unit of magnetic field as given in the graph attached is in milli-Tesla (mT) and the current is given in Ampere.
(i) What type of energy conversion is observed in a linear solenoid?
(a) Mechanical to Magnetic (b) Electrical to Magnetic
(c) Electrical to Mechanical (d) Magnetic to Mechanical
(ii) What will happen if a soft iron bar is placed inside the solenoid?
(a) The bar will be electrocuted resulting in short-circuit.
(b) The bar will be magnetised as long as there is current in the circuit.
(c) The bar will be magnetised permanently.
(d) The bar will not be affected by any means.
(iii) The magnetic field lines produced inside the solenoid are similar to that of …
(a) a bar magnet (b) a straight current carrying conductor
(c) a circular current carrying loop (d) electromagnet of any shape
(iv) After analysing the graph a student writes the following statements.
I. The magnetic field produced by the solenoid is inversely proportional to the current.
II. The magnetic field produced by the solenoid is directly proportional to the current.
III. The magnetic field produced by the solenoid is directly proportional to square of the current.
IV. The magnetic field produced by the solenoid is independent of the current.
Choose from the following which of the following would be the correct statement(s).
(a) Only IV (b) I and III and IV (c) I and II (d) Only II
(v) From the graph deduce which of the following statements is correct.
(a) For a current of 0.8A the magnetic field is 13 mT
(b) For larger currents, the magnetic field increases non-linearly.
(c) For a current of 0.8A the magnetic field is 1.3 mT
(d) There is not enough information to find the magnetic field corresponding to 0.8A current.
Our Environment
1. Food chains are very important for the survival of most species.
(i) If 10,000 J solar energy falls on green plants in a terrestrial ecosystem, what percentage of solar energy will be converted into food energy?
(a) 10,000 J (b) 100 J (c) 1000 J (d) It will depend on the type of the terrestrial plant.
(ii) If Ravi is consuming curd/yogurt for lunch, which trophic level in a food chain he should be considered as occupying?
(a) First trophic level (b) Second trophic level (c) Third trophic level (d) Fourth trophic level
(iii) The decomposers are not included in the food chain. The correct reason for the same is because decomposers:
(a) Act at every trophic level of the food chain
(b) Do not breakdown organic compounds
(c) Convert organic material to inorganic forms
(d) Release enzymes outside their body to convert organic material to inorganic forms
(iv) Matter and energy are two fundamental inputs of an ecosystem. Movement of
(a) Energy is bidirectional and matter is repeatedly circulating.
(b) Energy is repeatedly circulation and matter is unidirectional.
(c) Energy is unidirectional and matter is repeatedly circulating.
(d) Energy is multidirectional and matter is bidirectional.
(v) Which of the following limits the number of trophic levels in a food chain?
(a) Decrease in energy at higher trophic levels (b) Less availability of food (c) Polluted air (d) Water
2. Observe the following diagram and answer the questions any four from (i) and (v)
(i) Choose the waste management strategy that is matched with correct example.
(a) Refuse Choose products that use less packaging
(b) Reduce Give unwanted toys and books to hospitals or schools
(c) Reuse Not using single use plastic
(d) Repurpose Making flower pot from used plastic bottle
(ii) Recycling of paper is a good practice but recycled paper should not be used as food packaging because
(a) recycled papers may release color /dyes on food items
(b) recycled papers are not absorbent
(c) recycled papers can cause infection due to release of methane
(d) recycled papers are costly
(iii) According to the ‘Solid Waste Management Rule 2016’, the waste should be segregated into three categories. Observe the table below and select the row that has correct information
(iv) Effective segregation of wastes at the point of generation is very important. Select the appropriate statements giving the importance of waste segregation.
I. less waste goes to the landfills
II. better for public health and the environment
III. help in reducing the waste
IV. resulting in deterioration of a waste picker’s health
(a) both I and II (b) both I and III (c) both II and III (d) both I and IV
(v) The given graph shows the amount of waste generated, dumped and treated in percentage. Identify the reason of low success rate of waste management process.
(a) only 15% of urban India’s waste is processed
(b) less than 60% of waste is collected from households
(c) more than 60% of waste is collected from households
(d) both (a) and (b)
3. Biosphere is a global ecosystem composed of living organisms and abiotic factors from which they derive energy and nutrients. And ecosystem is defined as structural and functional unit of the biosphere comprising of living and non-living environment that interact by means of food chains and chemical cycles resulting in energy flow, biotic diversity and material cycling to form a stable, self-supporting system
(i) Which trophic level is incorrectly defined?
(a) Carnivores – secondary or tertiary consumers
(b) Decomposers – microbial heterotrophs
(c) Herbivores – primary consumers
(d) Omnivores – molds, yeast and mushrooms
(ii) The diagram below shows a food web from the sea shore
The mussel can be described as
(a) Producer (b) Primary consumer (c) Secondary consumer (d) Decomposer
(iii) The given figure best represents:
(a) Grassland food chain (b) Parasitic food chain (c) Forest food chain (d) Aquatic food chain
(iv) Consider the following statements concerning food chains:
(i) Removal of 80% tigers from an area resulted in greatly increased growth of vegetation
(ii) Removal of most of the carnivores resulted in an increased population of herbivores.
(iii) The length of the food chains is generally limited to 3 – 4 trophic levels due to energy loss
(iv) The length of the food chains may vary from 2 to 8 trophic levels
Which two of the above statements are correct?
(a) (i), (iv) (b) (i), (ii) (c) (ii), (iii) (d) (ii), (iv)
(v) Which of the following group of organisms are not included in ecological food chain?
(a) Carnivores (b) Saprophytes (c) Herbivores (d) Predators