Answer:
C. Diamond
Explanation:
Talc is the softest and diamond is the hardest. Each mineral can scratch only those below it on the scale.
Answer:
IV
Explanation:
Entropy is a measure of the degree of disorderliness in a particular molecule. What we are saying is that randomization plays an important role in the quest for determining a molecule at a point of disorderliness.
Now let us look at the answer choices.
N2 is a gas and is expected to have a high amount of degree of disorderliness.
SiO2 although is at the absolute zero temperature which is supposed to necessitate a low entropy amount, the fact that it is not ordered I.e amorphous confers a degree of disorderliness in its molecule.
NaCl although perfectly ordered is not at the absolute zero and hence cannot exhibit the needed degree of disorderliness.
Na is our answer choice because it meets the two criteria needed for zero entropy. Firstly, it is of considerable orderliness and hence, entropy isn’t expected in its molecule. Also, it has no disturbance in the case of temperature as it is at absolute zero.
Explanation:
1)  + 7 H_2(g)](https://tex.z-dn.net/?f=%202%20Al%28s%29%20%2B%202%20NaOH%28aq%29%20%2B%206%20H_2O%28l%29%20%5Clongleftrightarrow%202%20Na%5BAl%28OH%29_4%5D%28aq%29%20%2B%207%20H_2%28g%29)
![Kc=\frac{[Na[Al(OH)_4]]^2*[H_2]^7}{[NaOH]^2}](https://tex.z-dn.net/?f=Kc%3D%5Cfrac%7B%5BNa%5BAl%28OH%29_4%5D%5D%5E2%2A%5BH_2%5D%5E7%7D%7B%5BNaOH%5D%5E2%7D)
The Kc for the reverse reaction is the inverse of the Kc of the reaction:
2) 
![Kc=\frac{[H_2SO_4]}{[SO_3]^2}](https://tex.z-dn.net/?f=Kc%3D%5Cfrac%7B%5BH_2SO_4%5D%7D%7B%5BSO_3%5D%5E2%7D)
The Kc for the reverse reaction is the inverse of the Kc of the reaction:
3) 
![Kc=\frac{1}{[O_2]^3}](https://tex.z-dn.net/?f=Kc%3D%5Cfrac%7B1%7D%7B%5BO_2%5D%5E3%7D)
The Kc for the reverse reaction is the inverse of the Kc of the reaction:
Answer:
10.80
Explanation:
As per the equation, let us calculate the mole ratio. N2+3H2→2NH3. As per the equation one mole of nitrogen reacts with 1 mol of hydrogen.
In terms of mass. 28.01 g of nitrogen needs 3 mol of hydrogen or 6.048 g of hydrogen.
We can set up the ratio;
28.01 g of
l
N
2
needs
6.048 g of
l
H
2
1 g of
l
N
2
needs
6.048
28.01
g of
l
H
2
50.0 g of
l
N
2
needs
6.048
×
50.0
28.01
l
g of
l
H
2
=
10.80 g of
l
H
2
