Answer:
Explanation:
Speed of light = Wavelength x Frequency.
605 nm x Frequency = 3x10^8 m/s
6.05 x 10^-7 m x Frequency = 3x10^8 m/s
Frequency = 4.96 x 10^14 Hz
Ionic compounds are formed by a positive ion called cation and a negative ion called anion.
I will show you some examples:
NaCl is formed by the cation Na+ and the anion Cl -
CaF2 is formed by the cation Ca 2+ and the anion F -
Li2O if formd by the cation Li + and the anion O 2-.
To tell that you use the oxidation number of each element. I did it this way
Ca F2 => Ca has oxidation number 2+ and F has oxidation number 1- then the ions have that very same charge number.
If you follow the octet rule, you know that an element must have 8 outside (or valence) electrons to be energetically favorable.
In CCl4, the carbon molecule forms four bonds; one for each chlorine atom. Each bond contains 2 electrons, so it is satisfied.
In PCl3, Phosphorous forms only 3 bonds with chlorine, which means in order to have 8 valence electrons, it also has a lone pair of electrons, not bonded with chlorine.
Now, in CCl4, picture the shape of the molecule like a plus sign, with the carbon in the middle and the chlorine at the four ends. It is symmetrical, and therefore is nonpolar.
In PCl3, the lone pair electrons <em>push</em>, so to speak, the 3 chlorine atoms away, making a T-shaped molecule. Since the chlorine is more electronegative than carbon, the molecule is unbalenced, making it polar.
Volvox and paramecium live in the same living conditions. The visible difference between volvox and paramecium is
the shape. <span>Volvox is rounded, while paramecium is lying</span>.
