65 grams of HCl = 65/36.5 moles of HCl = 1.78 moles 1.78 moles of HCl dissolved to make a 5 litres of solution has a concentration of 1.78/5 = 0.36 mol/dm^3 (Note: 1 litre = 1 cubic decimetre)
In a strong acid, such as HCl, [H+] = [acid], so [H+] = 0.36
To calculate pH, we have to take the negative logarithm of the concentration of protons
I chose this because it seems more reasonable . Because its in the air so im guess that its gravitational bc to stay on top of a hill you need balance . Im sorry if its wrong k . I tried .