Hey there!
H₃PO₄
Find molar mass.
H: 3 x 1.008 = 3.024
P: 1 x 30.97 = 30.97
O: 4 x 16 = 64
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97.994 grams
The mass of 1 mole of H₃PO₄ is 97.994 grams.
We have 4.5 moles.
97.994 x 4.5 = 440
The mass of 4.5 moles of H₃PO₄ is 440 grams.
Hope this helps!
Answer: C2HNO3
Explanation: C = 27.59/12.011 = 2.297
H = 1.15/1.008 = 1.1409
N = 16.09/14.007 = 1.1487
O = 55.17/15.999 = 3.4483
Divide by smallest result:
C = 2
H=1
N=1
O = 3
Empirical formula = C2HNO3
Answer : The equilibrium concentration of
in the solution is, 
Explanation :
The dissociation of acid reaction is:

Initial conc. c 0 0
At eqm. c-x x x
Given:
c = 

The expression of dissociation constant of acid is:
![K_a=\frac{[H_3O^+][C_6H_5COO^-]}{[C_6H_5COOH]}](https://tex.z-dn.net/?f=K_a%3D%5Cfrac%7B%5BH_3O%5E%2B%5D%5BC_6H_5COO%5E-%5D%7D%7B%5BC_6H_5COOH%5D%7D)

Now put all the given values in this expression, we get:
![6.3\times 10^{-5}=\frac{(x)\times (x)}{[(7.0\times 10^{-2})-x]}](https://tex.z-dn.net/?f=6.3%5Ctimes%2010%5E%7B-5%7D%3D%5Cfrac%7B%28x%29%5Ctimes%20%28x%29%7D%7B%5B%287.0%5Ctimes%2010%5E%7B-2%7D%29-x%5D%7D)

Thus, the equilibrium concentration of
in the solution is, 
Both AM and FM radio signals have the same frequencies at times.
Answer:
B. Design homes that can be built on stilts where flooding is likely to occur.
C. Replace power lines that have been damaged by severe weather.
Explanation:
