Answer:
MgCl2 = 24 + 2(35.5)
= 95
mass of substance = mol × molar mass
= 0.119 × 95
= 11.305 g
72g H2O x 1 mol H2O/18.02g H2O = 3.99 mol H2O
Answer: solid
Explanation:In a solid, the atoms are closely packed and hence are close together. This results in a definite pattern of packing and a definite shape. Solids have a defined shape and volume as a result of this orderly arrangement of atoms very close to each other in the solid material.
The integrated rate law for a second-order reaction is given by:
![\frac{1}{[A]t} = \frac{1}{[A]0} + kt](https://tex.z-dn.net/?f=%20%5Cfrac%7B1%7D%7B%5BA%5Dt%7D%20%3D%20%20%20%5Cfrac%7B1%7D%7B%5BA%5D0%7D%20%2B%20kt%20)
where, [A]t= the concentration of A at time t,
[A]0= the concentration of A at time t=0
<span>k =</span> the rate constant for the reaction
<u>Given</u>: [A]0= 4 M, k = 0.0265 m–1min–1 and t = 180.0 min
Hence, ![\frac{1}{[A]t} = \frac{1}{4} + (0.0265 X 180)](https://tex.z-dn.net/?f=%20%5Cfrac%7B1%7D%7B%5BA%5Dt%7D%20%3D%20%5Cfrac%7B1%7D%7B4%7D%20%2B%20%280.0265%20X%20180%29%20)
<span> = 4.858</span>
<span><span><span>Therefore, [A]</span>t</span>= 0.2058 M.</span>
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<span>Answer: C</span>oncentration of A, after 180 min, is 0.2058 M