Answer:
+2
Explanation:
Alkaline earth metals are present in group 2 of periodic table. There are six elements in second group. Beryllium, magnesium, calcium, strontium, barium and radium.
All have two valance electrons.
Electronic configuration of Beryllium:
Be = [He] 2s²
Electronic configuration of magnesium.
Mg = [Ne] 3s²
Electronic configuration of calcium.
Ca = [Ar] 4s²
Electronic configuration of strontium.
Sr = [Kr] 5s²
Electronic configuration of barium.
Ba = [Xe] 6s²
Electronic configuration of radium.
Ra = [ Rn] 7s²
They are present in group two and have same number of valance electrons (two valance electrons) and show oxidation state +2 by loosing two valance electrons. They also show similar reactivity.
They react with oxygen and form oxide.
2Ba + O₂ → 2BaO
2Mg + O₂ → 2MgO
2Ca + O₂ → 2CaO
this oxide form hydroxide when react with water,
BaO + H₂O → Ba(OH)₂
MgO + H₂O → Mg(OH)₂
CaO + H₂O → Ca(OH)₂
With sulfur,
Mg + S → MgS
Ca + S → CaS
Ba + S → BaS
1. 2650000
2. 2410
3. 48100
For any given shell the number of subshells can be found by l = n -1. This means that for n = 1, the first shell, there is only l = 1-1 = 0 subshells.
Answer:
Marine life is least affected by the temperature fluctuations of the atmosphere.
Explanation:
The high specific heat capacity of water means that it takes much more energy to raise the temperatures of water by one (1) degree than land. This means that on a hot sunny day, land temperatures would increase dramatically while ocean temperatures would only rise slightly. Conversely, at night, the land cools rapidly while oceans cool slowly hence the temperatures drop slightly.
Answer:
True
Explanation:
Microscope is an instrument which is used to observe small objects. There are many types of microscope with a different magnitude.
