The percentage of hydrogen in C7H18 is calculated as follows:
[18/(12*7+1*8)]*100=18%
The amount of hydrogen in 5.2moles is given by:(18/100)*5.2=0.94moles
Answer: This was because the experiment showed that a substance could emit radiation even while it was not exposed to light.
It's adenosine triphosphate !
it has Penrose sugar and phosphate as backbone !
and nitrogenous base ... adenine.... in the middle !
Answer: If a hydrogen atom and a helium atom have the same kinetic energy then the wavelength of the hydrogen atom will be roughly equal to the wavelength of the helium atom.
Explanation:
The relation between energy and wavelength is as follows.

This means that energy is inversely proportional to wavelength.
As it is given that energy of a hydrogen atom and a helium atom is same.
Let us assume that
. Hence, relation between their wavelengths will be calculated as follows.
... (1)
... (2)
Equating the equations (1) and (2) as follows.

Thus, we can conclude that if a hydrogen atom and a helium atom have the same kinetic energy then the wavelength of the hydrogen atom will be roughly equal to the wavelength of the helium atom.
Answer:

Explanation:
» The prediction is 98% correct because single displacement reaction type is highly possible.
This is because Fluorine has is more electronegative than Chlorine in Potassium Chloride. So, it strongly displaces Chlorine from the solution hence forming Chlorine gas.
» The 2% of wrong prediction maybe because of wrong reactant measurements following mole concept chemistry.
If you are asked the observation,
Observation » <u> </u><u>A</u><u> </u><u>green</u><u> </u><u>yellowish</u><u> </u><u>gas</u><u> </u><u>is</u><u> </u><u>formed</u><u>.</u>
This gas is Chlorine gas (Cl2)