The answer should be "by convection" not by radiation.
Answer:
for the given reaction is -99.4 J/K
Explanation:
Balanced reaction: 
![\Delta S^{0}=[1mol\times S^{0}(NH_{3})_{g}]-[\frac{1}{2}mol\times S^{0}(N_{2})_{g}]-[\frac{3}{2}mol\times S^{0}(H_{2})_{g}]](https://tex.z-dn.net/?f=%5CDelta%20S%5E%7B0%7D%3D%5B1mol%5Ctimes%20S%5E%7B0%7D%28NH_%7B3%7D%29_%7Bg%7D%5D-%5B%5Cfrac%7B1%7D%7B2%7Dmol%5Ctimes%20S%5E%7B0%7D%28N_%7B2%7D%29_%7Bg%7D%5D-%5B%5Cfrac%7B3%7D%7B2%7Dmol%5Ctimes%20S%5E%7B0%7D%28H_%7B2%7D%29_%7Bg%7D%5D)
where
represents standard entropy.
Plug in all the standard entropy values from available literature in the above equation:
![\Delta S^{0}=[1mol\times 192.45\frac{J}{mol.K}]-[\frac{1}{2}mol\times 191.61\frac{J}{mol.K}]-[\frac{3}{2}mol\times 130.684\frac{J}{mol.K}]=-99.4J/K](https://tex.z-dn.net/?f=%5CDelta%20S%5E%7B0%7D%3D%5B1mol%5Ctimes%20192.45%5Cfrac%7BJ%7D%7Bmol.K%7D%5D-%5B%5Cfrac%7B1%7D%7B2%7Dmol%5Ctimes%20191.61%5Cfrac%7BJ%7D%7Bmol.K%7D%5D-%5B%5Cfrac%7B3%7D%7B2%7Dmol%5Ctimes%20130.684%5Cfrac%7BJ%7D%7Bmol.K%7D%5D%3D-99.4J%2FK)
So,
for the given reaction is -99.4 J/K
Answer:
B) Symmetrical and nonpolar
Step-by-step explanation:
The formula is H-C≡C-H.
Each C atom has <em>two</em> electron regions, so VSEPR theory predicts a <em>linear molecular geometry</em> (see image below).
The molecule is symmetrical, because the green line divides the molecule into two halves that are mirror images of each other.
The C-H bonds are slightly polar, because C is more electronegative than H (µ ≈ 0.4 D).
The C atoms are partially negative (red), while the H atoms are partially positive (blue).
However, the two C-H bond dipoles point in <em>opposite directions</em>, so they cancel each other. The molecule has <em>no net dipole moment.</em>
Acetylene is nonpolar.
M1m1 = M2m2
where M1 is the concentration of the stock solution, m1 is the
mass of the stock solution, M2 is the concentration of the new solution and
m2 is its new mass.
M1m1 = M2m2
.925(m1) = .35(250)
m1 = 94.59 g