What is the periodic table?

Which is true of transition metals when moving from left to right on the periodic table? the d sublevels are not filled across the period. the cation radii become larger across the period. atomic radii increase slightly and then start to decrease. atomic radii decrease slightly and then start to increase. o

The reaction q+r2=r2q is found to be first order in r2 and

If e is the symbol for an element, which two of the following symbols represent isotopes of the same element? 1. e2. e3. ea.1 and 2c.1 and 4b.3 and 4d.2 and 3