Does anyone know how to write out the formula for these?? not just the answer x

g Using the complex based titration system: 50.00 mL 0.00250 M Ca2 titrated with 0.0050 M EDTA, buffered at pH 11.0 determine (i

kobusy [5.1K]

Answer:

Explanation:

a).

conc of Ca²⁺ =0.0025 M

pCa = -log(0.0025) = 2.6

logK,= 10.65 So lc = 4.47 x 10.

Formation constant of Ca(EDTA)]-z= 4.47 x 10¹⁰ At pH = 11, the fraction of EDTA that exists Y⁻⁴ is $\alpha_{Y^{-4}}$ =0.81

So the Conditional Formation constant= $K_f$ =0.81x 4.47 x10¹⁰

=3.62x10¹⁰

b)

At Equivalence point:

Ca²⁺ forms 1:1 complex with EDTA At equivalence point,

Number of moles of Ca²⁺= Number of moles of EDTA Number of moles of Ca²⁺ = M×V = 0.00250 M × 50.00 mL = 0.125 mol

Number of moles of EDTA= 0.125 mol

Volume of EDTA required = moles/Molarity = 0.125 mol / 0.0050 M = 25.00 mL

V e= 25.00 mL

At equivalence point, all Ca²⁺ is converted to [CaY²⁻] complex. So the concentration of Ca²⁺ is determined by the dissociation of [CaY²⁻] complex.

$[CaY^{2-}] = \frac{Initial,moles,of, Ca^{2+}}{Total,Volume} = \frac{0.125mol}{(50.00+25.00)mL} = 0.001667M$

${K^'}_f$

Ca²⁺ + Y⁴ ⇄ CaY²⁻

Initial 0 0 0.001667

change +x +x -x

equilibrium x x 0.001667 - x

${K^'}_f = \frac{[CaY^{2-}]}{[Ca^{2+}][Y^4]}=\frac{0.001667-x}{x.x} =\frac{0.001667-x}{x^2}\\\\x^2 = \frac{0.001667-x}{{K^'}_f}\\ \\$

$x^2=\frac{0.001667}{3.62\times10^{10}}=4.61\exp-14$

x = 2.15×10⁻⁷

[Ca+2] = 2.15x10⁻⁷ M

pca = —log(2 15x101= 6.7

3 0

4 years ago

Which organ system carries materials to human tissues?

weqwewe [10]

Answer:

Cardiovascular they carry according to me

7 0

3 years ago

A drought has affected an ecosystem. Many plants have died due to lack of water. What do you think will happen ti the other orga

IceJOKER [234]

I think eventually other organisms will die out as well because many herbivores feed on plants for survival, and many other animals feed on these herbivores for survival and so on (this causes a chain reaction because there is a lack of available food)<span />

5 0

3 years ago

3 Pieces of Key Information elements, compounds, mixtures also state a real world example of elements, compounds, mixtures and l

Margarita [4]

Answer:

Element and compounds are the pure substances but mixture is not a pure substance.

Explanation:

Element and compounds are the pure substances in which element comprise of only one atom while compound is formed by the chemical combination of more than one element in a fixed ratio by mass while mixture is also made up of more that one substances but they are combine physically not chemically. Elements, compounds, mixtures are very important because all the materials we used in our daily life are formed from elements, compounds and mixtures.

8 0

3 years ago

When determining the cell potential for a hypothetical galvanic cell containing two different materials, how do we determine whi

dedylja [7]

To determine the substance that comprises the anode and the cathode in a galvanic cell is by determing ;

The material with the larger (more positive) standard reduction potential that will be the cathode.

<h3>Characteristics of a galvanic cell</h3>

In a galvanic cell, oxidation which leads to the loss of elctrons occurs at the anode, while reduction ( addition of elctrons ) occurs at the cathode. therefore the materials with a more positive standard reduction potential will be the cathode of the galvanic cell.

Hence we can conclude that The material with the larger (more positive) standard reduction potential will be the cathode.

Learn more about Galvanic cell : brainly.com/question/25606597

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8 0

3 years ago