What is the reason to have price on y-axis and quantity on x-axis while illustrating demand and supply curves?

Question

What is the reason to have price on y-axis and quantity on x-axis while illustrating demand and supply curves?

Answer 1

Because we lack basic knowledge of wealth. Quantity demanded/supplied is a form of wealth where as price is ratio of two forms of wealth (money and goods). If economics were defined as chemistry (study of nature, composition, laws, properties and classification) of wealth we would have taken goods (quantity demanded/supplied) along x axis and money ( demand/supply in money terms) along y axis and price would have become slope of the curve. Both goods demanded/supplied and demand/supply in money terms are forms of wealth. We would have been mathematically foolproof.  

Answer 2

no specific reason. . just the convention as alot of things in different subjects are kept as are in convention. . as far as i remember this convention was first set by Marshall while plotting the demand curve