The electromagnetic is a force that combines the effects of electrical charge and magnetism. The electromagnetic force can either attract or repel the particles on which it acts.
B. she can ask people about their backgrounds
This requires listening, the rest do not
Potassium +calcium sulphate ------> K2SO4+Ca
The correct option is D.
Mole is a measurement used in chemistry which allows us to measure out the same quantity of matter in different substances. Mole allows scientist to measure two substances, for instance, magnesium and sodium, which have equal amount of atoms. Thus, a mole of magnesium contains the same number of atoms as a mole of sodium.
Answer:
Option(II) and option (IV) are correct.
Explanation:
Here products are 
and 
and reactant is 
(I) According to Le-chatelier principle,increase in will shift the equilibrium towards reactant side to keep the equilibrium constant unchanged.
(II) According to Le-chatelier principle,decrease in will shift the equilibrium towards product side to keep the equilibrium constant unchanged.
(III) Adding a catalyst will not change position of equilibrium. Catalyst only helps to achieve equilibrium in a lesser time.
(IV) As this reaction is an endothermic reaction therefore heat is consumed in formation of product. Therefore increase in temperature will lead to formation of more product to consume excess heat added.
(V) Pure solids and liquids do not affect position of equilibrium as their concentrations remain unchanged.
