The ceiling fan direction in winter should be rotating clockwise or reverse. Warm air rises and gets trapped near the ceiling so when the ceiling fan direction is in reverse mode it circulates the warm air from the ceiling to the floor helping take the chill out of the air.
A reactant is a substance that is being used up or consumed in a chemical reaction. It is needed in large amount as compaed to reagent. A reagent is something which is used to initiate a reaction and aids to carry out it and it is also consumed in a reaction, unlikely to catalysts which are not consumed in a reaction.
Reaction quotient. In chemistry, a reaction quotient (Qr) is a function of the activities or concentrations of the chemical species involved in a chemical reaction. In the special case that the reaction is at equilibrium the reaction quotient is constant and equal to the equilibrium constant that appears in the expression of the law of mass action. A general chemical reaction in which Î± moles of a reactant A and Î² moles of a reactant B react to give Ï moles of a product R and Ï moles of a product S can be written as