Answer:
16
Explanation:
4 nitrogen (N) atoms and 12 (3×4) atoms in Hydrogen (H)
Total = 4 + 12 = 16 molecules
Answer:
D. Many, many years of deposition
Explanation:
The layers of the rocks in one region of the parks are smooth and distinct, which are evidence of many, many years of deposition.
The layers on the rocks are because of different deposition of sediments. Different sediments deposited over the rocks through wind, water and ice over the ages.
Hence, the correct answer is D.
MgSO4 + 2NaOH —> Mg(OH)2 + Na2SO4
Explanation:
A column on the periodic table represents a period.
These are some of the variations observed across a period;
- Atomic radii decreases progressively from left to right due to the progressive increase in the nuclear charge without an attendant increase in the number of electronic shells.
- Ionization energy increases progressively from left to right due to decreasing atomic radii.
- Electronegativity increases from left to right.
- Electropositivity decreases across a period.
