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.
Answer:
0.64 g of S
Solution:
The balance chemical equation is as follow,
2 Cu + S ----> Cu₂S
According to equation,
127 g (2 mole) Cu produces = 159 g (1 mole) of Cu₂S
So,
2.54 g Cu will produce = X g of Cu₂S
Solving for X,
X = (2.54 g * 159 g) / 127 g
X = 3.18 g of Cu₂S
Now, it is confirmed that the reaction is 100% ideal. Therefore,
As,
127 g (2 mole) Cu required = 32 g (1 mole) of S
So,
2.54 g Cu will require = X g of S
Solving for X,
X = (2.54 g * 32 g) / 127 g
X = 0.64 g of S
<u>Answer:</u>
Exothermic Reaction are those reaction, in which energy is released while in endothermic reaction are those, in which energy is absorbed.
<u>Explanation:</u>
First Reaction:
As in this reaction, energy is released
½H2(g) + ½I2(g) → HI(g), ΔH = +6.2 kcal/mole
so it is <em>exothermic reaction</em>
Second reaction:
As in this reaction, energy is absorbed
21.0 kcal/mole + C(s) + 2S(s) → CS2(l)
so it is <em>endothermic reactions</em>.
It is softer than topaz and and it is softer than diamond (diamond has a Mohs hardness of 10, which is the highest value of the scale)
Answer:
D. exosphere is the outer layer of the thermosphere
