Its arbitrary. It was developed on the greek phoenetic system and never reallybwas explained.
Answer:
Moving Across a Period
Moving from left to right across a period, the atomic radius decreases. The nucleus of the atom gains protons moving from left to right, increasing the positive charge of the nucleus and increasing the attractive force of the nucleus upon the electrons
Because all atoms are made from the same particles which are protons, neutrons, and electrons.
Hope this helped!!!
Answer:
The discipline of Earth and space science is concerned with the study of the planets and stars is
A. Astronomy
Explanation:
A.Astronomy:
'Astron' means stars and 'nomos' means laws. So astronomy is the study of stars , planets and space
B.
biology
It is derived from Greek word : 'Bios' means life and 'logos' means study.
Biology is study of life, living organism ,structure of organisms,evolution
C.Geology
It is the earth science which includes the study of rocks and solid earth, what it is made of and how it has changed .
D. Oceanography
It is the study of physical and biological aspects of oceans