The answer is A. The vibration caused by the waves through the air eventually weaken, which is why sound diminishes easily over distance.
Answer:
D) CN⁻
Explanation:
Hund's Rule of Maximum Multiplicity state that electrons go into degenerate orbitals of sub-levels (p,d, and f ) singly before pairing commences. Hund's rule is useful in determining the number of unpaired electrons in an atom. As such, it explains some magnetic properties of elements.
An element whose atoms or molecules contain unpaired electrons is paramagnetic. i.e., weakly attracted to substances in a magnetic field.
On the other hand, the element whose atoms or molecules are filled up with paired electrons is known as diamagnetic, i.e., not attracted by magnetic substances.
According to the molecular orbital theory, the diamagnetic molecule is CN⁻ because of the absence of unpaired electrons.
Answer:
Carbon
Explanation:
Carbon has four electrons in its valence shell, so it generally shares it in a covalent bond. This element needs four electrons to be stable, so it can form single (such as the bond with hydrogen), double (such as the bond with oxygen) or triple bonds (such as the bond with nitrogen).
It can also form bonds with other carbon, and they can form longs chains, that's why there are a lot of organic compounds (the compounds with carbon). Carbon can form rings too, such as in benzene.
Answer:
Regions of the Electromagnetic Spectrum
Wavelength (m)Frequency (Hz)Radio> 1 x 10-1< 3 x 109Microwave1 x 10-3 - 1 x 10-13 x 109 - 3 x 1011Infrared7 x 10-7 - 1 x 10-33 x 1011 - 4 x 1014Optical4 x 10-7 - 7 x 10-74 x 1014 - 7.5 x 1014
