Give the symbol of the element that has the largest atomic size in group 3a (13).

This family of elements is headed by boron. In this case, atomic size increases as one goes down the periodic table, as there are more electrons in each successive element needed to fill the outer shells. As such, thallium, at the lowest level of the group 3a column, will have the largest atomic size.

1. Mass of Al lost = 
A. 0.31 g 

2. Moles of Al lost= 0.31 g / 27.0 g/mol = 0.011 g Al 
C. 0.011 moles 

3. Mass of Pb=4.26 - 0.92 = 3.34 g 
B. 3.34 g 

4. Moles of Pb formed= 3.34 g / 207.2 g/mol = 0.016 mol Pb 
A. 0.016