Answer:
Base Mg(OH)2 does neutralise the acid and is 12g in excess.
Explanation:
2HCL +Mg(OH)2 -> MgCl2 + 2H20
2 * 36.458 g of HCL react with 58.319 g of Mg(OH)2 to neutralise it.
72.916 HCl reacts with 58.319 g of the base.
So 20 g HCl reacts with (58.319/72.916) * 20 = 16g.
There are 28 g of Mg(OH)2 so the base does neutralise all the acid.
The Mg(OH)2 is 28 - 16 = 12 g in excess.
Answer:
The greenhouse effect is a natural process that warms the Earth's surface. ... The absorbed energy warms the atmosphere and the surface of the Earth. This process maintains the Earth's temperature at around 33 degrees Celsius warmer than it would otherwise be, allowing life on Earth to exist.
Answer:
Temperature & Humidity
Explanation:
If the body could not adapt to these changes, we wouldn't be able to live all over the planet; from the equator up to the polar caps.
Missing in your question :
Ksp of(CaCO3)= 4.5 x 10 -9
Ka1 for (H2CO3) = 4.7 x 10^-7
Ka2 for (H2CO3) = 5.6 x 10 ^-11
1) equation 1 for Ksp = 4.5 x 10^-9
CaCO3(s)→ Ca +2(aq) + CO3-2(aq)
2) equation 2 for Ka1 = 4.7 x 10^-7
H2CO3 + H2O → HCO3- + H3O+
3) equation 3 for Ka2 = 5.6 x 10^-11
HCO3-(aq) + H2O(l) → CO3-2 (aq) + H3O+(aq)
so, form equation 1& 2&3 we can get the overall equation:
CaCO3(s) + H+(aq) → Ca2+(aq) + HCO3-(aq)
note: you could get the overall equation by adding equation 1 to the inverse of equation 3 as the following:
when the inverse of equation 3 is :
CO3-2 (aq) + H3O+ (aq) ↔ HCO3- (aq) + H2O(l) Ka2^-1 = 1.79 x 10^10
when we add it to equation 1
CaCO3(s) ↔ Ca2+(aq) + CO3-2(aq) Ksp = 4.5 x 10^-9
∴ the overall equation will be as we have mentioned before:
when H3O+ = H+
CaCO3(s) + H+(aq) ↔ Ca2+ (aq) + HCO3-(aq) K= 80.55
from the overall equation:
∴K = [Ca2+][HCO3-] / [H+]
when we have [Ca2+] = [HCO3-] so we can assume both = X
∴K = X^2 / [H+]
when we have the PH = 5.6 so we can get [H+]
PH = - ㏒[H+]
5.6 = -㏒[H]
∴[H] = 2.5 x 10^-6
so, by substitution on K expression:
∴ 80.55 = X^2 / (2.5 x10^-6)
∴X = 0.0142
∴[Ca2+] = X = 0.0142
You need to monitor the solution to see when the crystals start gathering at the bottom of the solution. You can slowly add alum until it stops dissolving. The point just before it starts its sedimentation at the bottom is the point when the solution is saturated.