What is the mass of element P which reacts with 1 .62g of element Q to form a compound with formula Q2p3 (relative atomic mass p,16;Q,27)

Mass of element P = 1.44 g

Proust stated the Comparative Law that compounds are formed from elements with the same Mass Comparison so that the compound has a fixed composition of elements

In the same compound, although from different sources and formed by different processes, it will still have the same composition/comparison

MW Q₂P₃ = 2.27 + 3.16=102 g/mol

Mass Q₂P₃ (MW=102 g/mol) :

Mass P (Ar=16) :

or you can solve it with mol :

Reaction

3P + 2Q ⇒ Q₂P₃

mol Q :

mol P :

mass P :

nacl is added to the aqueous of what? ? in order to get a proper answer you have to specify the exact composition of the aqueous solution.

b. accuracy of the data matters alot more than its number of digits, organization or amount of detail. quantitative observation is more accepted than the qualitative observation.