Your answer is B. or 2 - After it has hit the ground.
I took this quiz today and got this correct
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
Answer:
When the concentration of F- exceeds 0.0109 M, BaF2 will precipitate.
Explanation:
Ba²⁺(aq) + 2 F⁻(aq) <----> BaF₂(s)
When BaF₂ precipitates, the Ksp relation is given by
Ksp = [Ba²⁺] [F⁻]²
[Ba²⁺] = 0.0144 M
[F⁻] = ?
Ksp = (1.7 × 10⁻⁶)
1.7 × 10⁻⁶ = (0.0144) [F⁻]²
[F⁻]² = (1.7 × 10⁻⁶)/0.0144 = 0.0001180555
[F⁻] = √0.0001180555 = 0.01086 M = 0.0109 M
Hope this Helps!!!
Answer:
compound
Explanation:
We already know that the original substance was pure. If this substance was pure and it was powdery in nature then we have a footing to start from.
Secondly, a 4.93 g of shinny metallic liquid was left behind. This shinny metallic liquid must be an element.
Since there was a loss in mass during heating, it follows that there were other components of the pure powder.
If the reasoning stated above is correct, then the substance is a compound.
