Arrange from highest to lowest in order of decresing mass:

1 gg, 100 g, 1 kg, 50 cg, 1 cg, 1 dg, 50 million ng

Highest to lowest in order of decreasing mass:

1 Gg> 1 kg> 100 g >50 cg> 1 dg > 50 million ng > 1 cg

Explanation:

1) 1 Gg = 1,000,000,000 g

1 giga gram=  

2) 100 g

3) 1 kg = 1000 g

1 kilogram = 1000 grams

4) 50 cg = 0.5 g

1 centigram = 0.01 gram

5)1 cg =0.01 g

1 centigram = 0.01 gram

6) 1 dg = 0.1 g

1 decigram = 0.1 gram

7) 50 million ng =

1 nanogram = grams

From highest to lowest in order of decreasing mass

1,000,000,000 g > 1000 grams> 100 g> 0.5 g>0.1 g>0.05 g>0.01 g

1Gg> 1 kg> 100 g >50 cg> 1dg > 50 million ng > 1 cg

since the atomic number is the number of protons in the nucleus, as we move to the left on the periodic table, the electrostatic pull between the nucleus and the valence electron shell decreases. as we move down a group (vertical column), the valence shell energy level gets further and further from the nucleus.