Answer:
A and C represent elements while B and D represent Compounds
Explanation:
chemical elements cannot be broken down into simpler substances by any chemical reaction. While A chemical compound is a chemical substance composed of many identical molecules composed of atoms from more than one element held together by chemical bonds
Answer: (C)
The frequency increases as the wavelength decreases
Explanation:
The relation between the frequency and wavelength of a wave is
Frequency = 1 / Wavelength
The Frequency of electromagnetic wave is inversely proportional to the wavelength. So, as the frequency increases, the wavelength of the wave decreases and vise-versa.
The frequency of a wave is number of complete cycles passing a particular point per second. Its S.I unit is Hertz whereas the wavelength of a wave is the distance between two consecutive crest and trough in meters.
So, on increasing the frequency of a wave, there will be more number of the cycles of wave per second which will decrease the distance between the consecutive crest and trough i.e wavelength.
The answer:
for the monoatomic <span>selenium ions
</span> -the ion charge of selenium is 2-, so the answer is [Se]2+
as for the monoatomic phosphorus ions
-the ion charge of phosphorus is 3-, so the answer is [P]3-
Answer:
Atoms bonds with 8 electrons
Explanation:
Octet rule is a chemical rule that shows elements in main group bond so that each atom have 8 valence electrons in the outmost shell which make them to have similar electronic configuration with Noble gases This is important because the sharing of electrons make atoms to have full shell. Atoms with electrons not up to 8 react with more stable compound.
