Answer:increasing the concentration of reactants
Explanation:
Collision is the phenomenon in which the reactant molecules come to nearest closness,as a result the reactants are converted into products.
Now the number of effective collision is directly proportional to the number of reactants added..
As a base is added to an acidic solution, the H+ ions in solution that make it acidic are slowly neutralized into water (via OH-, the base). As these ions are converted into water the concentration of them decreases, so the pH decreases, as they are directly related.
Hope this helps!
Since obliquity is the angle between the axis of rotation and the direction perpendicular to the orbital plane, it changes as the orbital plane changes due to the influence of other planets. But the axis of rotation can also move (axial precession), due to torque exerted by the sun on a planet's equatorial bulge.
(Got it from google )