The substances present before the reaction are the reactants. (As the reaction goes through, the substances that are produced are called the products of the reaction).
Combination
Hope this helps :)
Answer:- Mole ratio of D to A is 4:3.
Explanations:- Mole ratio for a chemical reaction is the ratio of the coefficients.
The given generic chemical reaction is:

The numbers written in front of each chemical species in the chemical reaction are their moles. For the given generic chemical reaction the coefficient of A is 3 and that of B is 1. So, the mole ratio of A to B is 3:1.
Similarly if we want to write the mole ratio of C to D then it is 1:4.
We are asked to write the mole ratio of D to A. So, like the other ratios, the mole ratio of D to A is 4:3 as the coefficient of D is 4 and A is 3.
ANSWER: C) Law of Conservation of Mass
EXPLANATION: In the given cycle, it is seen that th sediments are layered and gets compressed into sedimentary rocks which eventually gets heated and compressed to form metamorphic rocks. But, the total amount of minerals present in the sediments remains the same throughout any stage of the cycle.
This proves the law of conservation of mass which states that mass can not be created nor be destroyed, it can only be transferred from one form to another. So, in this case, only phase transition occurred but the component which is mineral inside the sediments remains constant.
Therefore, the answer is law of conservation of mass.
Answer:
hi
Explanation:
it is confusing lol
but i think that it is C.both
hope it helps
have a nice day