a. The unit cell is the smallest group of atom which have overall symmetry of a crystal, and from which is the entire letters can be buled built up by repetition in 3 dimensions.
b. The volume(v) of the unit cell is equal to the cell edge length (a)cubed.
c. density of polonium is 9.32g/cm3.
Answer:
You may, but it is too risky.
Even though you are being cautious around using electric equipment around water, you'll never know what can happen. You might accidentally drop that piece of electrical equipment you are using into the water. Water can be splashed around by someone or something without you noticing it and it may affect the object you are using. Sometimes, if water comes in contact with an electrical object, it may cause you electric shocks or the equipment you are using has a chance of exploding and may hurt you. You can guarantee that waterproof electrical equipment is safe to use, but it is better not to risk it too much.
Answer:
The noble gases (Group 18) are located in the right of the periodic table and were previously referred to as the "inert gases" due to the fact that their filled valence shells (octets) make them extremely nonreactivE
Explanation:
Answer:
By absorbing energy electron is jump into higher energy level. This is called excitation.
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.
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.
B radiation therapy is mainly used to destroy cancer cells and as a cancer treatment.
