science 12 grade

Question: The K, L and M shells of an atom are full. Its atomic number is_______. 1. 18 2. 20 3. 10 4. 12 Answer: ..

All the elements belonging to 3 to 12 groups are called transition elements. They resemble each other in several physical and chemical properties. They are all metals. They are called transition elements because they are placed between the most reactive metals on the left and non-metals ..

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. For example, if 11 protons, 11 electrons and 12 neutrons are present in an atom, it forms an atom of sodium. But if 79 protons, 79 electrons and 118 neutrons are present in an atom, then we have an atom of gold. We are now in a position of explain why the atomic mass of carbon is 1..

Question: The resistance of an electric bulb drawing 1.2 A current at 6.0 V is ___________. 1. 0 .5 W 2. 5 W 3. 0.2 W 4. 2 W Answer: ..

Question: A source of frequency of 500 Hz emits waves of wavelength 0.4 m, how long does the waves take to travel 600 m? 1. 3 s 2. 6 s 3. 9 s 4. 12 s Answer: ..

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 12 O 6 + 6O 2 6CO 2..

Mass of the body (m) = 5 kg Velocity of the body (v) = 15 m/s Kinetic energy Kinetic energy = 562.5 J 02. A dog of mass 20 kg is running at a constant speed of 12 m/s. Calculate the kinetic energy of the dog while it is runni..

When a small piece (pea size) of sodium is placed in cold water, it darts about on the water with a hissing sound and produces hydrogen. The water left behind, acquires the property of turning red litmus blue. This shows the presence of a basic substance, which is sodium hydroxide. ..

Represent the atom of sodium whose atomic mass is 23 and atomic number is 11. Calculate the number of protons, electrons and neutrons..