science 12 grade

Question: An atom has a mass number of 23 and atomic number 11. The number of protons are_________. 1. 11 2. 12 3. 23 4. 44 Answer: ..

Question: Four elements along a period have atomic number (11, 13, 16 and 17). The most metallic among these has an atomic number of __________. 1. 11 2. 12 3. 16 4. 17 Answer: ..

Question: An object is placed 12 cm from a convex lens whose focal length is 10 cm. The image must be. 1. virtual and enlarged 2. virtual and reduced in size 3. real and reduced in size 4. real and enlarged Answer: ..

Question: Give the general equation for respiraton. Answer: C 6 H 12 O 6 +6O 2 6CO 2 +6H 2 O+38A..

Question: A body moving along a straight line at 20 m/s undergoes an acceleration of 4 m/s 2 . After two seconds its speed will be ________. 1. 8 m/s 2. 12 m/s 3. 16 m/s 4. 28 m/s Answer: ..

Question: Six elements A, B, C, D, E and F have the following atomic numbers (A = 12, B = 17, C = 18, D = 7, E = 9 and F = 11). Among these elements, the element, which belongs to the 3 rd period and has the highest ionisation potential, is __________. 1. A 2. B 3. C ..

Question: What are hydrocarbons? Answer: Compounds containing only the elements carbon and hydrogen are called hydrocarbons. They are a parent class of organic carbon compounds from which all other classes of hydrocarbon sub groupings of compounds can be made. Examples: Ethane (C 2 H 4 )..

Respiration - Meaning - Respiration can be broadly defined as "the breakdown of organic compounds into simpler compounds accompanied by the release of energy in the form of ATP" Since most often the substrate is glucose, the general equation for respiration can be written as follows: C 6 H 12h..

Molecular weight of N 2 = 2 x 14 = 28 g28 g of N 2 at STP occupies = 22.4 L 2.8 g of N 2 at STP = ?28 g of N 2 = 22.4 L2.8g of N 2 = ? 2.8 g of N 2 at STP occupies a volume of 2.24..

Question: A ray of light travels from a medium of refractive index n 1 to a medium of refractive index n 2 . If angle of incidence is i and the angle of refraction is r. Then is equal to 1. n 1 2. n 2 3. n 21 4. n 12 Answer: ..