Q. Sodium (Na), Magnesium (Mg), Aluminium (Al) and Silicon (Si) are arranged in the decreasing order of their atomic size. Which element has the highest ionisation energy among them? Justify your answer scientifically.

Q. Write any two advantages of bioenergy.

Q. (a) How is dermal tissue adapted to prevent excessive transpiration in plants?
(b) Why do leaves of lotus plant float on water?

Q. Haemoglobin levels in the blood samples of two persons A and B are found to be 9 gm/dL and 13 gm/dL respectively. Which statement is true with respect to the amount of oxygen supply in their body?

1. More in person B than in person A
2. More in person A than in person B
3. Equal in person A and person B
4. No correlation between oxygen supply and the level of haemoglobin

Q. Urban people should be encouraged to take up the practice of roof-top gardening. Justify.

Q. What is pulping? How is an uncoated paper converted into coated paper?

Q. Scelerenchyma fibres are used in coir industries to make gunny bags and ropers. Give scientific reason.

Q. No image is formed on the blind spot of human eye because

1. Cones are absent
2. Rods are absent
3. Optic nerve is absent
4. Rods and cones are absent

Q. Mention the properties of silica due to which it is used as sand bath in laboratory.

Q. Significant reduction in the platelet count of human blood is the main symptom of this disease.

1. Chikungunya
2. Dengue
3. Bird flu
4. Gonorrhea

Q. Match the following

Q. Differentiate between Caucasoid man and Mongoloid man based on their physical features.

Q. Identify one of the uses of solar heater in the following.

1. Conversion of solar energy into electrical energy
2. Providing energy for artificial satellites
3. Desalination of marine water
4. Using in automatic streelights

Q. Lymph plays an important role in protecting immune system of the body. Justify this statement.

Q. Draw the diagram of blast furnance used in the extraction of iron?

Q. What is forward biasing and reverse biasing of a diode?

Q. While doing the experiment of copper voltmeter, in which of the following cases, more amount of copper gets deposited at cathode?

1. 2 amperes of electric current is passed for 30 minutes
2. 4 amperes of electric current is passed for 20 minutes
3. 0.5 amperes of electric current is passed for 80 minutes
4. 1.5 amperes of electric current is passed for 30 minutes

Q. Name the two important non-metallic oxides which causes acid rain.

Q. Identify the correct complementary base pairing among the following.

1. Adenine - Thymine and Guanine - Cytosine
2. Adenine - Guanine and Thymine - Cytosine
3. Adenine - Cytosine and Thymine - Guanine
4. Guanine - Adenine and Cytosine - Adenine

Q. Draw the diagram of a DC dynamo and label the following parts :
a) Split rings
b) Armature coil

Q. $Si+C\to$ SiC. This chemical reaction is an example for:

1. endothermic reaction
2. exothermic reaction
3. dissociation reaction
4. displacement reaction

Q. What is red shift?

Q. The densities of 4 gases at standard temperature and pressure are given in the table

Gas	Methane	Ammonia	Helium	Neon
Density	0.72 g/L	0.77 g/L	0.18 g/L	0.90 g/L

Among these gases, which gas diffuses very fast? State the law that helps you to take the decision.

Q. Hydroponic and aeroponic methods are gaining significance in space research organisations. Give two reasons for this.

Q. In Fleming's right hand rule middle finger indicates the direction of

1. Magnetic field
2. Induced electric current
3. Mechanical energy
4. Motion of the conductor

Q. What are extrinsic semicunductors? Name the two types of extrinsic semiconductors.

Q. A domestic electrical appliance requires alternating current of 15 V. If 220 V of alternating current is supplied to the house, then the device that helps in the functioning of that electrical appliance is

1. Induction coil
2. Step-up transformer
3. AC dynamo
4. Step-down transformer

Q. What are ultrasonic waves? Write any two uses of ultrasonic waves in the field of medicine.

Q. Find out the most efficient engine in the following

1. An engine converts 80 KJ of heat energy into 20 KJ of work
2. An engine converts 50 KJ of heat energy into 15 KJ of work
3. An engine converts 30 KJ of heat energy into 6 KJ of work
4. An engine converts 60 KJ of heat energy into 24 KJ of work

Q. What is annealing of glass? Name the colour obtained when (i) Ferric compounds, (ii) Cobalt compounds are added to the mixture of molten glass.