Structure of At...

A certain sample of element Z contains 60% of $${ 69 }_{ Z }$$ and 40% of $$71_{ Z }$$. What is the relative atomic mass of element Z in this sample.

Moseley's equation is represented as $$\sqrt { v } =a(Z-b)$$ where a and b are constants If $$OA=1$$, then atomic number of the elements showing frequency of $$400Hz$$ is?

Visible spectrum lies between:

What is the potential energy of an electron present in N-shell of the $${ B }e^{ 3+ } ion$$?

The orbit from which when electron will jump in other orbit, energy may be absorbed but not emitted out, will be?

The mass of an element $$E$$ found in $$1.00\ mole$$ of each of four different compounds is $$38.0\ g$$, $$57.0\ g$$, $$76.0\ g$$ and $$114\ g$$ respectively . 

$$4.16 g$$ of $$BaCI_{2}$$ contains $$2.74 g$$ of Ba. The atomic weight of Ba is nearly:

If the ratio of the radius of the two different nuclei is 2:3; then what will be the ratio of their mass? 

Suppose that A and B form the compounds $$B_2A_3$$ and $$B_2A$$. If 0.05 mole of $$B_2A_3$$ weighs 9 g and 0.1 mole of $$B_2A$$ weighs 10 g, the atomic weight of A and B respectively are: