The structure of tofacitinib with explicit carbon and hydrogen is the first attached picture.
The number of carbon atoms in tofacitinib are 16.
The molecular formula of tofacitinib is
.
The structure of tofacitinib with all the filled hydrogen atoms is the second attached picture.
Answer:
4.48 grams of potassium hydroxide that the chemist must be weighing out.
Explanation:
The pH of the KOH solution = 13
pH + pOH = 14
pOH = 14 - pH = 14 - 13 = 1
![pOH=-\log[OH^-]](https://tex.z-dn.net/?f=pOH%3D-%5Clog%5BOH%5E-%5D)
![1=-\log[OH^-]](https://tex.z-dn.net/?f=1%3D-%5Clog%5BOH%5E-%5D)
![[OH^-]=0.1 M](https://tex.z-dn.net/?f=%5BOH%5E-%5D%3D0.1%20M)

1 mole of hydroxide ions are obtained from 1 mole of KOH. Then 0.1 mole of hydroxide ions will be obtained from :
of KOH
![[Molarity]=\frac{\text{Moles of solute}}{\text{Volume of solution(L)}}](https://tex.z-dn.net/?f=%5BMolarity%5D%3D%5Cfrac%7B%5Ctext%7BMoles%20of%20solute%7D%7D%7B%5Ctext%7BVolume%20of%20solution%28L%29%7D%7D)
Volume of KOH solution = 800 mL = 0.800 L ( 1 mL = 0.001 L)

Moles of KOH = 0.1 M × 0.800 L = 0.08 mol
Mass of 0.08 moles of KOH :
0.08 mol × 56 g/mol = 4.48 g
4.48 grams of potassium hydroxide that the chemist must be weighing out.
here we have to explain the development of the atomic theory by the atomic emission spectrum.
The most important aid in determining the structure of an atom has been study of radiation emitted and absorbed by the elements. The glowing atoms of an element emit radiations.
These are called the atomic spectra. This study helped to understand the structure of the atoms.
To explain the atomic spectra the Bohr's model was introduced. The postulates of the Bohr's model explain the fine spectrum of the atom up to the particle nature of the electrons.
Later some modification on the Bohr's postulates was made to explain the wave nature of the electrons as well. But the atomic spectra is best be understood by the Bohr's atomic model which developed the atomic theory.
Thus the understanding of emission spectrum of atom to develop the atomic theory is explained.
Answer:
Option E
Explanation:
As work is dot product of force and displacement
W=FdCos0
As Cos 0=1 so W=F.d(1)
W=F.d
as Cos 90=0 so no work will be done when angle between force and displacement is 90 degree. At angle between force and displacement is 180 degree then negative value com as Cos 180= -1