15.5% by mass is
equivalent 15.5 g urea in 100 g solution or 155 g urea in 1 kg solution. <span>
<span>we know that molality = moles solute / kg solvent
<span>moles solute = 155 g / 60 g/mol = 2.58 moles urea
</span></span></span>
Since there are 155 g
urea in 1000g solution, hence the solvent is 845 g or 0.845 kg
So:<span>
<span>molality = 2.58 / 0.845 = 3.06 m</span></span>
For the excited state of Ca at the absorption of 422.7 nm light,the energy difference is mathematically given as
E= 4.70x10-22 kJ/mol
<h3>What is the energy difference (kJ/mole) between the ground and the first excited state?</h3>
Generally, the equation for the Energy is mathematically given as
E = nhc / λ
Where
h= plank's constant
h= 6.625x 10-34 Js
c = speed of light
c= 3x 108 m/s
Therefore
E = 1*(6.625x 10-34 Js)( 3x 10^8 m/s) / ( 422.7x10^-9)
E= 4.70x10-22 kJ/mol
In conclusion, Energy
E= 4.70x10-22 kJ/mol
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The dehydration of cyclopentanol is shown in the balanced equation below:
Cyclopentanol => cyclopentene + H2O
Therefore, the alkene produced from the dehydration of cyclopentanol is cyclopentene.
The OH group is removed from the compound resulting to an alkene, cyclopentene. <span />
Liquid makes up most of the body
