When a solid forms with two solutions are mixed it is a precipitate

Blank # 1 - keep safe distance from the burner
Blank # 2 - Place the equipments on the right place after use
Blank # 3 - perform experiments with proper lab equipment and safety tools
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(maybe it can be hazardous)
From the given observations,
You can see that as the concentration is doubled, half-life is halved.
That is,half-life is inversely proportional to concentration
As t( half-life) ~ 1/a^(n-1)
For this case n = 2,second order reaction.
R = k X a^n
Using the above formula you will get the rate and rate constant.
Answer: E = (13.6 eV) [1/nf² - 1/ni²]
En = (-13.6 eV)/n²
where n=1,2,3...
Explanation:
According to Bohr's theory each spcified energy value( E1,E2,E3...) is called energy level of the atom and the only allowable values are given by the equation
En = (-13.6 eV)/n²
The energy change (ΔE) that accompaies the leap of an electron from one energy level to another is given by equation
E = (13.6 eV) [1/nf² - 1/ni²]