Rubidium would exhibit the greatest shielding [ effect. ]
Apples turn brown when exposed to air because it undergoes aerial oxidation. Due to this, when the inside of the apple is exposed to the air containing oxygen and water, it turns brown. When apple is uncut, skin of the apple protects it from this process.
If the peeled apple in kept in the refrigerator, the oxidation reaction is greatly slowed down. This is because, rate of chemical reaction decreases with temperature. Hence, in refrigerator it would take several days for it to turn brown.
Answer:
Pumice is a light colored, porous igneous rock. It forms during volcanic eruption occurring under water. It is an aggregate of concrete. Because of their porous nature they float over the surface of water. With time the pumice rocks undergoes with several changes including weathering, erosion, and transportation. The extent of heat and pressure, making the sediments of the pumice rocks into metamorphic rocks distinct in the chemical and physical composition of the parent material.
Answer:
When the excited electron fall back to the lower energy levels the energy is released in the form of radiations.The characteristics bright colors are due to the these emitted radiations. These emitted radiations can be seen if they are fall in the visible region of spectrum
Explanation:
The electron is jumped into higher level and back into lower level by absorbing and releasing the energy.
The process is called excitation and de-excitation.
Excitation:
When the energy is provided to the atom the electrons by absorbing the energy jump to the higher energy levels. This process is called excitation. The amount of energy absorbed by the electron is exactly equal to the energy difference of orbits. For example if electron jumped from K to L it must absorbed the energy which is equal the energy difference of these two level. The excited electron thus move back to lower energy level which is K by releasing the energy because electron can not stay longer in higher energy level and comes to ground state.
De-excitation:
When the excited electron fall back to the lower energy levels the energy is released in the form of radiations. this energy is exactly equal to the energy difference between the orbits. The characteristics bright colors are due to the these emitted radiations. These emitted radiations can be seen if they are fall in the visible region of spectrum
Answer:
Explanation:
A reactant is a substance that is present at the start of a chemical reaction. The substance(s) to the right of the arrow are called products . A product is a substance that is present at the end of a chemical reaction.
h2 + 02 = h2o
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