Answer:
0.0342 moles
Explanation:
Moles and Mass are related as,
Moles = Mass / M.Mass
M.Mass of NaCl = 58.44 g/mol
Putting values,
Moles = 2.00 g / 58.44 g/mol
Moles = 0.0342 moles
Answer:
Concentration: 0.185M HX
Ka = 9.836x10⁻⁶
pKa = 5.01
Explanation:
A weak acid, HX, reacts with NaOH as follows:
HX + NaOH → NaX + H2O
<em>Where 1 mole of HX reacts with 1 mole of NaOH</em>
To solve this question we need to find the moles of NaOH at equivalence point (Were moles HX = Moles NaOH).
18.50mL = 0.01850L * (0.20mol / L) = 0.00370 moles NaOH = Moles HX
In 20.0mL = 0.0200L =
0.00370 moles HX / 0.0200L = 0.185M HX
The equilibrium of HX is:
HX(aq) ⇄ H⁺(aq) + X⁻(aq)
And Ka is defined as:
Ka = [H⁺] [X⁻] / [HX]
<em>Where [H⁺] = [X⁻] because comes from the same equilibrium</em>
As pH = 2.87, [H+] = 10^-pH = 1.349x10⁻³M
Replacing:
Ka = [H⁺] [H⁺] / [HX]
Ka = [1.349x10⁻³M]² / [0.185M]
Ka = 9.836x10⁻⁶
pKa = -log Ka
<h3>pKa = 5.01</h3>
Distilling ocean water would be a good solution to meet this community's water needs because it will prevent some water borne diseases such as cholera, diarrhea, typhoid etc.
<h3>
Importance of water distillation</h3>
Water Distillation Systems has several advantages and some of the advantages include;
- It removes waterborne biological contaminants such as bacteria, viruses, organic and inorganic chemicals, heavy metals, etc
- It makes the water fit for consumption
Thus, distilling ocean water would be a good solution to meet this community's water needs because it will prevent some water borne diseases such as cholera, diarrhea, typhoid etc.
Learn more about water distillation here: brainly.com/question/3166914
#SPJ1
Answer:
-1,103.39KJ/mol
Explanation:
We use the subtract the standard enthalphies of formation of the reactants from that of the products. It must be taken into consideration that the enthalpy of formation of elements and their molecules alone are not taken into consideration. Hence, what we would be considering are the standard enthalpies of formation of H2S, H2O and SO2.
In places where we have more than one mole, we multiply by the number of moles as seen in the balanced chemical equations.
The standard enthalpies of the molecules above are as follows:
H2S = -20.63KJ/mol
H2O = -285.8KJ/mol
SO2 = -296.84KJ/mol
O2 = 0KJ/mol
ΔrH⦵ = [2ΔfH⦵(H2O) + 2 ΔfH⦵(SO2)] − [ΔfH⦵(H2S) + 3
ΔfH⦵(O2)]
ΔrH⦵ =[(2 × -285.8) + (2 × -296.84)]
-[ 3 × -20.63)]
= (-571.6 - 593.68 + 61.89) = -1,103.39KJ/mol
Explanation:
During the formation of BeCl2, the beryllium atom bonds with two chlorine atoms via single covalent bonds. The number of electron pairs around the central atom will be two. No lone pair is found in the molecule. If we analyse this information then we can conclude that BeCl2 has sp hybridization.
the cathode
