Answer:
Trough is the lower bound of wave, while the crest is the upper bound of a wave.
Explanation:
see picture attatched
Answer:
In a radio, chemical energy is transformed into sound energy
Answer: The correct answer is crude oil is a mixture of many organic compounds that need to be isolated to be used.
Explanation:
Crude oil is a naturally occurring petroleum product which is unrefined. It consists of various hydrocarbon deposits and organic compounds.
The refining of crude oil is important because it yield some important compounds that can be used in various purposes.
The refining of crude oil produces products such as gasoline, petrol, diesel and various other forms of petrochemicals which can be used on daily basis.
Hence, the correct statement is crude oil is a mixture of many organic compounds that need to be isolated to be used.
Answer: The correct option is e.
Explanation: In the given question it is asked to tell the element which has 'Sea of electrons' while bonding.
This means that the element should have extra electrons so that it can bond easily or this also means which element can easily donate its electron to form a bond.
- Electronic configuration of Hydrogen =

Hydrogen cannot loose electrons easily because the electron is present in 1s sub-shell which is the closest to the nucleus and hence will be tightly bonded to it.
- Electronic configuration of Helium =

This element will not loose electrons easily because the 1s sub-shell is fully filled and hence will not be available for bonding.
- Electronic configuration of Sulfur =

This element lacks 2 electrons from attaining stable configurations. Hence, it will gain 2 electrons rather than donating for bonding.
- Electronic configuration of Iodine =

This element lacks 1 electron to attain stable configuration. Hence, it will gain 1 electron rather than donating for bonding.
- Electronic configuration of Lithium =

This element has an extra electron in its valence shell and can be easily lost in order to form bond.
Hence, the correct option is e.