The three elements A, B and C with similar properties have atomic masses X, Y and Z respectively. This mass of Y is approximately equal to the average mass of X and Z. What is such an arrangement of elements called as ? Give on example of such a set of elements.

Three elements A, B and C with similar properties have atomic masses X,Y and Z respectively. The mass of Y is approximately equal to the average mass of X and Z. What is such an arrangement of elements called? Give one example of such a set of elements.

Three elements X , Y and Z have atomic numbers 19 , 37 and 55 respectively . Then the correct statement (s) is / are

Three elements X , Y and Z have atomic numbers 19 , 37 and 55 respectively . Then the correct statements (s) is / are

The atomic masses of three elements X,Y and Z having similar chemical properties are 7,23 and 39 respectively (a) Calculate the average atomic mass of elements X and Z (b) How does the averge atomic mass of elements X and Z compare with the atomic mass of element Y (c) Which law of classification of elements is illustrated by this example? (d) What could the elements X,Y and Z be? (e) Give another example of a set of elements which can be classified according to this law.

In a triad of three elements A, B, and C, the atomic mass of A and B are 80 and 120 respectively. Find the atomic mass of element C.