Answer:

Calculation of number of atoms in 2Xg of B

- Given, atomic weight of element A = 40 amu and atomic weight of element B = 80 amu
- Let Xg of A contain Y atoms, then Xg of A would have mass = 40Y amu
- Now, 2Xg of B would have mass = 2*X*80 amu = 160X amu
- We know that atomic weight (in amu) is directly proportional to the number of atoms present in the element
- Therefore, we can set up a proportion: (40Y amu) : Y atoms = (160X amu) : n atoms (where n is the number of atoms in 2Xg of B)
- Solving this proportion, we get n = 4YX atoms

Therefore, there are 4YX atoms present in 2Xg of B.

Importance and Scope of Chemistry

Chemistry is a branch of science that deals with the composition, structure, properties, and reactions of matter. It plays a crucial role in our daily lives and has a wide range of applications in various fields like medicine, engineering, agriculture, and many more. Some of the major importance and scope of chemistry are:

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