Answer:

Explanation:
Whenever a question asks you, "How long does it take to reach a certain concentration?" or something like that, you must use the appropriate integrated rate law expression.
The integrated rate law for a first-order reaction is
![\ln \left (\dfrac{[A]_{0}}{[A]} \right ) = kt](https://tex.z-dn.net/?f=%5Cln%20%5Cleft%20%28%5Cdfrac%7B%5BA%5D_%7B0%7D%7D%7B%5BA%5D%7D%20%5Cright%20%29%20%3D%20kt)
Data:
[A]₀ = 1.28 mol·L⁻¹
[A] = 0.17 [A]₀
k = 0.0632 s⁻¹
Calculation:
![\begin{array}{rcl}\ln \left (\dfrac{[A]_{0}}{0.170[A]_{0}} \right ) & = & 0.0632t\\\\\ln \left (5.882) & = & 0.0632t\\1.772 & = & 0.0632t\\\\t & = & \dfrac{1.772}{0.0632}\\\\t & = & \textbf{{28.0 s}}\\\end{array}\\\text{It will take } \boxed{\textbf{28.0 s}} \text{ for [HI] to decrease to 17.0 \% of its original value.}](https://tex.z-dn.net/?f=%5Cbegin%7Barray%7D%7Brcl%7D%5Cln%20%5Cleft%20%28%5Cdfrac%7B%5BA%5D_%7B0%7D%7D%7B0.170%5BA%5D_%7B0%7D%7D%20%5Cright%20%29%20%26%20%3D%20%26%200.0632t%5C%5C%5C%5C%5Cln%20%5Cleft%20%285.882%29%20%26%20%3D%20%26%200.0632t%5C%5C1.772%20%26%20%3D%20%26%200.0632t%5C%5C%5C%5Ct%20%26%20%3D%20%26%20%5Cdfrac%7B1.772%7D%7B0.0632%7D%5C%5C%5C%5Ct%20%26%20%3D%20%26%20%5Ctextbf%7B%7B28.0%20s%7D%7D%5C%5C%5Cend%7Barray%7D%5C%5C%5Ctext%7BIt%20will%20take%20%7D%20%5Cboxed%7B%5Ctextbf%7B28.0%20s%7D%7D%20%5Ctext%7B%20for%20%5BHI%5D%20to%20decrease%20to%2017.0%20%5C%25%20of%20its%20original%20value.%7D)
Answer:
In very hot, humid weather you might feel the air is heavier because moving around seems to take more energy than on dry days. Sticky days probably feel “heavier” because heat and high humidity slows the evaporation of perspiration, your body grows hotter and this saps your strength
Explanation:
Answer:polar covalent bond
Explanation:
Compounds are formed ether by donating, receiving or sharing of electrons making the bonds between them to be ionic, or covalent .
Now according to the rule of type of bond assignment due to electronegativity difference of atoms
---When the electronegativity difference is less than 0.5, the bond formed is nonpolar covalent.
---When the electronegativity difference is between 0.5 and 1.6, the bond is considered polar covalent
---When the electronegativity difference greater than 2.0, then the bond is ionic.
Therefore, When the absolute value of the difference in electronegativity of two adjacent atom in a compound is 1, they are most likely bonded by polar covalent bond eg HCl bond , CCL4 bond
Answer:
The molar mass of MgCI2 is 95.211 g/mol