Answer:
beryllium
Explanation:
Beryllium has 4 protons 5 nutrons and 6 electrons
This problem is providing information about possible causes whereby mussel shells are being eroded due to the acidity in the ocean. In such a way, it claims that more acidic oceans dissolve calcium carbonate in a faster way and produce hydrogen carbonate ions, and thus, a feasible explanation is required as well as a hypothesis according to the following choices:
a. Lower CO₂; this reduces the H₂CO₃ and increases the pH.
b. Add CO₃²⁻: this will add base and increase its concentration.
c. Add Ca²⁺: this will increase the precipitation rate of calcium carbonate (correct choice).
<h3>Equilibrium equations:</h3>
At first instance, we should recall the equilibrium equations that take place when acidic oceans dissolve calcium carbonate in a faster way:


<h3>Shifts from equilibrium:</h3>
Where we can see that the first choice is thoroughly discarded as the addition of CO₂ actually increases the ionizable carbonic acid (acidity). Moreover, the addition of CO₃²⁻ may also lead to the formation of more protons-releasing carbonic acid which also contributes to the acidity of the ocean.
<h3>Hypothesis:</h3>
Thereby, the correct condition that, for sure, contributes to the preservation of mussel shells will be the addition of Ca²⁺ and the hypothesis will be that it shifts the equilibrium towards the formation of more CaCO₃, the active compound in these shells.
Learn more:
The rows in the top third - This group consists of elements like Sodium, Magnesium, Potassium and Calcium on the right and Chlorine, Carbon, Nitrogen and Oxygen on the left.
Sodium and Chlorine are components of salt, a very important compound of our blood, essential for transferring electrical signals from the brain to the rest of the body and vice versa. Calcium is the building block of our bones, while Magnesium and potassium ensure proper functioning of our organs.
Very easy. use the following formula:
pH + pOH= 14
so pOH= 14-2.5= 11.5
3 lithium ions bond to one nitrogen ion.