The hardness of water is determined primarily by the amount of calcium and magnesium it contains. ... Instead of having higher levels of calcium and magnesium, soft water tends to have higher concentrations of sodium, or salt.
If the angle is either 0 or 180, that means that there is either negative or positive work, so A and D are not correct.
If the angle is 45, then there is still some work involved.
The only option where there is no work done by a force is B. when the angle is between the force and displacement is 90.
The correct answers are :
Changing the volume of the system.
Changing the temperature of the system.
Equilibrium will remain unaffected if the concentration of products and reactants are kept the same, and the temperature of the system is kept constant.
As the system is closed, we cannot add or remove products or reactants.
Change in temperature will shift the chemical equilibrium towards the reactant or product depending on whether the reaction is exothermic or endothermic.
Also change in volume will shift the chemical equilibrium of a chemical reaction if the reactants or products or both are gases.
