Answer:
when electron emit the radiations it means it jumped to the lower energy level from higher energy level.
Explanation:
When electron jump into lower energy level from high energy level it loses the energy.
The process is called 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.
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:
x
Explanation:
becaue neutron equal to mass num -atomic num
Explanation:
The solvent is a base or medium , in which reaction takes place ,
Mostly organic solvents have hydrogen and carbon , and is purposely used to dissolve the organic sample .
The example of organic solvents , used in laboratory are as follows -
1. Toluene
2. Hexane
3. Pentane
4. Benzene
5. Methanol
Answer and Explanation,
Sand dollar, any of the invertebrate marine animals of the order Clypeastroida (class Echinoidea, phylum Echinodermata) that has a flat, disk-shaped body. They are close relatives of sea urchins and heart urchins. The sand dollar is particularly well adapted for burrowing in sandy substrates. Very small spines used for digging and crawling cover the entire surface of its body and are appressed backwards toward the posterior anus. The mouth is located in the centre of the body’s underside. The upper surface exhibits pentaradiate symmetry, with a pattern of five “petals” spreading out from the centre. Some species found stranded on the shores of North America have five or six slots, or lunules, through the test (external skeleton). Most sand dollars measure from 5 to 10 cm (2 to 4 inches) in diameter. Species of comparable size occur in shallow coastal waters throughout the rest of the world, except in Europe and Antarctica.
