B ia the correct one .
Hydrogen only uses the first energy shell, which holds 2 electrons, not 8.
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
Answer: B
Nitrifying bacterium, plural Nitrifying Bacteria, any of a small group of aerobic bacteria (family Nitrobacteraceae) that use inorganic chemicals as an energy source.
The statement is false because endothermic reactions have a positive enthalpy change, because heat is being added to the system because it requires more energy to react
Answer:
16.0 g; 3.1 mol
Explanation:
(a) Mass of O atoms
Mass = 6.022 × 10^23 atoms × (2.66 × 10^-23 g/1 atom) = 16.0 g
(b) Moles of O atoms
0.050 kg = 50 g
Moles = 50 g × (1 mol/16.0 g) = 3.1 mol
