E = hf
c = speed of electromagnetic wave, c ≈ 3 * 10⁸ m/s,
Planck's constant h = 6.63 *10⁻³⁴ Js
h = Planck's constnat, Frquency, f = c/λ = (3*10⁸)/(488*10⁻⁹)
E = hf
E = hc/λ
E = (6.63 * 10⁻³⁴ * 3 * 10⁸) /(488 * 10⁻⁹)
Energy, E ≈ 4.0758 * 10⁻¹⁹ Joules.
Answer:
Amides are suitable to synthesize aniline
Explanation:
Amide are basically used to synthesize aniline.
The chemical formula of Aniline is C6H5NH2 while that of Amide is RCONH2
Amide are solids that can be easily converted to amines.
For the noble gasses, you get D, but metals are basically everywhere in the periodic table...
Answer: 2. cannot be an element.
Explanation:
Element is a pure substance which is composed of atoms of similar elements.It can not be decomposed into simpler constituents using chemical reactions.Example: Copper 
Compound is a pure substance which is made from atoms of different elements combined together in a fixed ratio by mass.It can be decomposed into simpler constituents using chemical reactions. Example: methane 

Thus as it can be decomposed into its constituent elements, it is a compound.
Mixture is a substance which has two or more components which do not combine chemically and do not have any fixed ratio in which they are present.
Thus methane cannot be an element.