<u><em>*(Answer)*=</em></u> An ion can have a positive or negative charge. Furthermore, it is a an atom or molecule with a net electric charge due to the loss or gain of one or more electrons.
<u><em>*(Request)*=</em></u> Searching the definition can help you find a definition faster.
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User who Answered: <u><em>BangtanBoyScouts</em></u>
Answer: it’s the third one
Explanation:
The rate law for the reaction : r=k.[A]²
<h3>Further explanation</h3>
Given
Reaction
A ⟶ B + C
Required
The rate law
Solution
The rate law is a chemical equation that shows the relationship between reaction rate and the concentration / pressure of the reactants
For the second-order reaction it can be:
1. the square of the concentration of one reactant.
![\tt r=k[A]^2](https://tex.z-dn.net/?f=%5Ctt%20r%3Dk%5BA%5D%5E2)
2. the product of the concentrations of two reactants.
![\tt r=k[A][B]](https://tex.z-dn.net/?f=%5Ctt%20r%3Dk%5BA%5D%5BB%5D)
And the reaction should be(for second order) :
2A ⟶ B + C
Thus, for reaction above (reactant consumption rate) :
![\tt r=-\dfrac{\Delta A}{2\Delta t}=k[A]^2](https://tex.z-dn.net/?f=%5Ctt%20r%3D-%5Cdfrac%7B%5CDelta%20A%7D%7B2%5CDelta%20t%7D%3Dk%5BA%5D%5E2)
To determine the quantity of pure CaCl2 from the given amount of CaCl2.9H2O, we use the ratio of CaCl2 to CaCl2.9H2O. From the formula the ratio would 1 is to 1 We calculate as follows:
7.5 g CaCl2.9H2O (1 mol / 273.1215 g) ( 1 mol CaCl2 / 1 mol CaCl2.9H2O ) ( <span>110.98 g / 1 mol ) = 3.05 g CaCl2
Hope this answers the question. Have a nice day. Feel free to ask more questions.</span>