Jawapan

2016-09-13T19:05:06+08:00
Acid plus alkali will equalize
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2016-09-14T08:52:37+08:00
You must make sure all the elements on both sides are equal in number. This involves simple mathematical calculation of multiplication. Let's look at this example :

1. Potassium reacts with hydrochloric acid, produces potassium chloride and hydrogen gas.

K + HCl ----> KCl + H₂

~ You have 1 each for K and Cl on the left and right side. However on the right side, there are 2 H, but 1 on the left side. Therefore, you need to add "2" for HCl.

K + 2HCl ----> KCl + H₂

~ The number of H is now balanced. But Cl is not. You have to add "2" to KCl. And when you do that, you need to add "2" to K as well so that the number for K is also balanced.

2K + 2HCl ----> 2KCl + H₂

* The above equation is balanced.
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