Is change in atmospheric co2 levels likely to impact marine life

The addition of carbon dioxide to the atmosphere takes place due to human activities like the burning of fossil fuels. The oceans play an essential role in maintaining the carbon cycle of the Earth in balance. With the elevation of carbon dioxide in the atmosphere, more absorption of carbon dioxide takes place by the oceans.  

In the ocean, carbon dioxide reacts with seawater to produce carbonic acid, this ultimately leads to an increase in acidity of seawater, also known as ocean acidification.  

With the increase in acidity, it becomes tougher for corals to construct skeletons and for shellfish and other creatures to manufacture the shells they require for protection. The corals are mainly essential as they offer habitation to various sea creatures.  

ΔH°r = -114.40 kJ

Explanation:

Let's consider the following balanced equation.

4 HCl(g) + O₂(g) ⇒ 2 H₂O(g) + 2 Cl₂(g)

We can calculate the standard enthalpy change of the reaction (ΔH°r) using the following expression.

ΔH°r = ∑np × ΔH°f(p) - ∑nr × ΔH°f(r)

where

ΔH°r = 2 mol × ΔH°f(H₂O(g)) + 2 mol × ΔH°f(Cl₂(g)) - 4 mol × ΔH°f(HCl(g)) - 1 mol × ΔH°f(O₂(g))

ΔH°r = 2 mol × (-241.82 kJ/mol) + 2 mol × 0 kJ/mol - 4 mol × (-92.31 kJ/mol) - 1 mol × 0 kJ/mol

ΔH°r = -114.40 kJ