Because the shielding effect(by the inner electrons) remains the same but the nuclear charge is increasing(due to the increasing number of protons)
So Chlorine has the highest number of protons...so its outter electrons tend to expierence the most nuclear attraction hence making it more harder to remove the first electron
Carbonated drinks have the air under pressure so that carbon bubbles are forced into the drink, keeping it carbonated. So when you open a can, the air under pressure in the can comes out of the can at a high speed, making a "whooshing" sound. The gas law that applies to this concept is the Boyle's Law (PV=k or P1V1=P2V2).
The pH of a solution is a measure of the molar concentration of hydrogen ions in the solution and as such is a measure of the acidity or basicity of the solution.
So, the form of scientific notation is 
