Answer:
In crystal structure close packing is define as space efficient arrangement of constituent particles to form a crystal lattice.
Explanation:
closest packing
In crystal structure close packing is define as space efficient arrangement of constituent particles to form a crystal lattice.
Difference between hexagonal closest packing and cubic closest packing
In cubic closest packing arrangement, each sphere is surrounded by 12 other spheres on the other hand in case of hexagonal close packing, layers of spheres are packed so that spheres in alternating layers overlie one another.
unit cell for each closest packing arrangement
The hexagonal closest packed arrangement has a coordination number of 12 and it consists of 6 atoms per unit cell. The face centered cubic lattice has a coordination number of 12 and it consists of 4 atoms per unit cell. In case of body centered cubic crystal the coordination number is 8 and it consists of 2 atoms per unit cell.
Elements are pure elements matter is atoms in general
Answer:
The correct answer is - sulfur.
Explanation:
In the periodic table, there are 18 groups and 7 rows or periods arranged according to their atomic number or electronic configuration. In the question, it is mentioned that the desired element atomic mass is less than the atomic mass of the selenium which is 78.96, and more than oxygen which is 15.99 with 6 electron valence and present in the third row.
As it has 6 valency of electron it must be in the 16 group of the table that comprises the 6 valency and as it is located in the 3rd row it must be sulfur that also has an atomic mass between selenium and oxygen.
<u>Answer:</u> The molar solubility of 
is 
<u>Explanation:</u>
Solubility is defined as the maximum amount of solute that can be dissolved in a solvent at equilibrium.
Solubility product is defined as the product of concentration of ions present in a solution each raised to the power its stoichiometric ratio.
The balanced equilibrium reaction for the ionization of calcium fluoride follows:
s 2s
The expression for solubility constant for this reaction will be:
![K_{sp}=[Pb^{2+}][I^-]^2](https://tex.z-dn.net/?f=K_%7Bsp%7D%3D%5BPb%5E%7B2%2B%7D%5D%5BI%5E-%5D%5E2)
We are given:
Putting values in above equation, we get:
Hence, the molar solubility of is
Answer : The initial temperature of system 2 is, 
Explanation :
In this problem we assumed that the total energy of the combined systems remains constant.
The mass remains same.
where,
= heat capacity of system 1 = 19.9 J/mole.K
= heat capacity of system 2 = 28.2 J/mole.K
= final temperature of system = 
= initial temperature of system 1 = 
= initial temperature of system 2 = ?
Now put all the given values in the above formula, we get
Therefore, the initial temperature of system 2 is,
