Answer: D : A is 3 : 2.
Explanation:
The law of definite proportion is being used here. The law states that a given compound always has the same proportion of its constituent elements by mass.
2a + b = c + 3d
This actually means that, two moles of “a” react with a mole of “b” to produce a mole of “c” and 3 moles of “d”
Using the concept of stoichiometry coefficients of d and a
d:a = 3:2
1) All matter is made of atoms. Atoms are indivisible and indestructible.
2) All atoms of a given element are identical in mass and properties
3) Compounds are formed by a combination of two or more different kinds of atoms.
4) A chemical reaction is a rearrangement of atoms.
1 and 2 were proved wrong.
The answer is Decomposition.