Arrange the following atoms in order of decreasing atomic radius, and account for the trend.

(a) Cr

(b) Ti

(c) Mn

(d) V

Video transcript

Hello, everyone. Today we have the following problem rank the falling transition metals in order of increasing atomic radius. So we have tech medium, rhenium molybdenum and Neo bum provide an explanation for the observed trend. So and twe A through D have some combination of these elements arranged and then they have the following explanations. So we need to find the trend for atomic radius. But before we do that, let's roughly sketch the position of these elements. And so they are all within the same period. So first, we essentially have the OBM followed by molybdenum and then we have our tech medium. And then lastly, we have our rhenium and atomic radius increases as we go from right to left on the periodic table. And so with that in mind, the largest atomic reus would be our niobium. And so that gets rid of choices B and D. So we like that choice is A and C. And so they both have the correct order which goes niobium molybdenum ruin and tech medium for in order of increasing atomic radius. But the explanations differ. So the correct answer is actually going to be a and that is because the observed trend of decreasing atomic radii from left to right across the periodic table across the period is caused by the increasing nuclear charge from left to right across the period. And so that essentially just means that if we were to look and gauge the number of protons from the periodic table as we go from right to left or from left to right, the number of protons increase. And so the protons will attract the negatively charged electrons, meaning that there's more positive charge in the nucleus as we go from left to right. So that essentially just gives us the correct answer of a and with that, we have solved the problem overall, I hope it's helped until next time.