The question is incomplete, the complete question is;
Which statement describes a difference between electromagnetic and mechanical waves?
A. Mechanical waves cannot be longitudinal, but electromagnetic waves can.
B. Electromagnetic waves cannot move particles, but mechanical waves can.
C. Electromagnetic waves do not require a medium, but mechanical waves do.
D. Mechanical waves do not transfer energy, but electromagnetic waves do.
Answer:
Electromagnetic waves do not require a medium, but mechanical waves do.
Explanation:
A wave is defined as a disturbance along a medium which transfers energy. Waves may be classified as mechanical waves or electromagnetic waves based on their medium of propagation.
A mechanical wave requires a material medium for propagation. An example of a mechanical wave is sound waves. Sound waves are propagated in air.
Electromagnetic waves do not require a material medium for propagation. They can travel through space. An example of electromagnetic waves is light waves.
B don’t know what light has to do with a ball bouncing
C. 25 Miles
This is because you have 12.5 moles of water and using the ratio this is 2 (molar ratio). Therefore the molar ratio for HF is 4, so 12.5 x 2 = 25 moles
Answer:
The answer is boiling point.
Explanation:
The boiling point of a substance refers to the temperature at which the vapour pressure of a liquid equals the atmospheric pressure; at this point the liquid will boil. Different liquids have different boiling points that are unique to them. This makes it possible for scientists to use boiling points as one of the criteria by which a liquid substance can be identified. At boiling point, the chemical bonds that are holding liquid particles together are destroyed and the liquid turn to gas.