Answer : The value of diffusion coefficient is, 
Explanation :
Formula used :

where,
D = diffusion coefficient = ?
= 
= 
R = gas constant = 8.314 J/mol.K
T = temperature = 
Now put all the given values in the above formula, we get:


Thus, the value of diffusion coefficient is, 
Answer: There are 0.056 moles present in 3.45 g of
.
Explanation:
Given : Mass = 3.45 g
Moles is the mass of substance divided by its molar mass.
Hence, moles of
(molar mass = 61.98 g/mol) is as follows.

Thus, we can conclude that there are 0.056 moles present in 3.45 g of
.
Answer:
High conductivity
Explanation:
Metals exhibit high conductivity due to the mobility of valence electrons.
Answer:
The first row fits in period 2
The second row fits in period 3
Explanation:
Elements arranged vertically in the periodic table in groups that share similar chemical properties.
Elements are also organized horizontally in rows or periods
The length of each period is determined by the number of electrons that can occupy the sublevels being filled in that period.
Answer:
Umm i dont know but i think atomic nucleus
Explanation: