Answer:
The only PH range which is not covered by any of the given components of the universal indicator is 7.6-8.0
Hence the PH range 7.6-8 can't be described using universal indicator.
All of them are compounds.
Answer:
Since the noble gases are unreactive or inert, they are safe to use. Helium is used to fill balloons and airships, because it is much lighter that air and it will not catch fire. Neon is used in advertising signs. It will give red glow, but the color can be changes by mixing it with other gases.
Explanation: