Caffeine that is C8H10N402 is molecule which made up of 4 different elements. apart from carbon the other element includes
element symbol
nitrogen N
oxygen O
hydrogen H
The number of atom present in caffeine molecule are as follows
Nitrogen=4 atoms
Oxygen=2 atoms
Hydrogen=10 atoms
Answer:
Sulfur (Option-C) <span>exhibits chemical behavior similar to that of oxygen.
Explanation:
Sulfur has same chemical properties as that of Oxygen because both of them belongs to same group in the periodic table. Also, the similarity of chemical behaviour among the group members is due to same number of electrons in their valence shells.
For examole, the electronic configuration of Oxygen is,
1s</span>², 2s², 2p⁴
There are six valence electrons in the valence shell (i.e. 2) of Oxygen.
Now for Sulfur,
1s², 2s², 2p⁶, 3s², 3p⁴
There are six valence electrons in the valence shell (i.e. 3) of Sulfur.
Therefore, both elements tends to gain 2 electrons in a reaction and form O⁻² and S⁻² respectively.
D. How the pull of gravity has changed.
Answer : The correct answer for change in freezing point = 1.69 ° C
Freezing point depression :
It is defined as depression in freezing point of solvent when volatile or non volatile solute is added .
SO when any solute is added freezing point of solution is less than freezing point of pure solvent . This depression in freezing point is directly proportional to molal concentration of solute .
It can be expressed as :
ΔTf = Freezing point of pure solvent - freezing point of solution = i* kf * m
Where : ΔTf = change in freezing point (°C)
i = Von't Hoff factor
kf =molal freezing point depression constant of solvent.
m = molality of solute (m or
)
Given : kf = 1.86 
m = 0.907
)
Von't Hoff factor for non volatile solute is always = 1 .Since the sugar is non volatile solute , so i = 1
Plugging value in expression :
ΔTf = 1* 1.86
* 0.907
)
ΔTf = 1.69 ° C
Hence change in freezing point = 1.69 °C
Answer:
four million two hundred and thirty
Explanation: