Answer:
<h2>7.6</h2>
Explanation:
The pH of a solution can be found by using the formula
![pH = - log [ {H}^{+} ]](https://tex.z-dn.net/?f=pH%20%3D%20-%20log%20%5B%20%7BH%7D%5E%7B%2B%7D%20%5D)
From the question we have
We have the final answer as
7.6
Hope this helps you
1. False
2. True
3. True
4. False
5. True.
6. False.
7. True.
8. False.
9. False.
10. True.
11. False.
<h3><u>Explanation</u>:</h3>
A wave is a disturbance in a medium which can propagate through a medium. But the net displacement of the medium remains zero.
The spreading of the wave from a slit or hole is proved through the double slit experiment showing interference between the two waves. So they do spread by passing through a hole.
A longitudinal wave is what is seen when a stone is thrown into a pond. The ripples created are the compression points and the areas between the two ripple is called the rarefaction point.
Amplitude is defined as the maximum displacement of a particle in wave from its mean position. So its not distance between two compression points.
2nd law of reflection states that the angle of incidence is equal to angle of reflection.
An electromagnetic wave doesn't need a matter to get transferred. Its the electric field and magnetic field vibrating at same interval but in 90°to each other.
Mechanical wave needs matter to transfer energy. So it cannot travel through space.
Decibel is the unit of intensity of sound. Unit of frequency is hertz or cps.
Dull (not shiny)
poor conductors of heat and electricity (they are insulators)
weak and brittle (they easily break or shatter when solid)
Answer:
during reaction magnesium lises ions.
Explanation:
magnesium reacts by losing two ions which makes it smaller in size.
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
