<h3>
Answer:</h3>
1.380 × 10^-8 M
<h3>
Explanation:</h3>
The pH is the measure of alkalinity or acidity of a substance.
It is the negative logarithm of H+ ions concentration [H+].
pH = -log[H+]
pOH on the other hand is negative logarith of OH- concentration [OH-].
pOH = -log[OH-]
In this case;
pOH = 7.86
We can calculate the [OH-]
pOH = -log[OH-]
But, pOH = 7.86
pOH = -log[OH-]
-log[OH-] = 7.86
[OH-] = Antilog -7.86
= 1.380 × 10^-8 M
Therefore, [OH-] is 1.380 × 10^-8 M
There are certain processes in nature that produce many of these radioactive<span>isotopes. For instance, some </span>radioactive<span> nitrogen is produced in the atmosphere when high energy cosmic radiation from the sun hits the earth. Other </span>radioactive<span>isotopes are only available by artificial production. good luck</span>
Answer : Chemicals A and B form an endothermic reaction, and chemicals C and D form an exothermic reaction.
Explanation :
Endothermic reaction : When the system absorb heat from the surrounding then the surrounding become cool.
Exothermic reaction : when the system releases heat into the surrounding then the surrounding become hot.
According to the question,
when we mixed chemical A and chemical B together in a test tube to form chemical C, the mixture become cool. This means that the system is absorbing heat from the surrounding and thus the reaction is called a endothermic reaction.
And when we added chemical D in chemical C, the new mixture becomes hot and explodes. This means that the system is releasing heat into the surrounding and thus the reaction is called as exothermic reaction.
Answer:
As temperature increases, molecules gain energy and move faster and faster. Therefore, the greater the temperature, the higher the probability that molecules will be moving with the necessary activation energy for a reaction to occur upon collision.
Explanation:
hope this helps!
