Calculate the density in g/cm3 for the mass of 452.1g and volume of 292cm3

15g of FeCI3 is dissolved in 450 mL of solution. What is the concentration of [CI-]?

storchak [24]

The concentration of [CI-] : 0.617 M

<h3>Further explanation</h3>

FeCl₃ dissolved in 450 mL of solution(will dissociate )

Reaction

FeCl₃⇒Fe³⁺+3Cl⁻

mol FeCl₃(MW=162,2 g/mol)

$\tt \dfrac{15}{162.2}=0.0925$

mol Cl⁻ :

$\tt \dfrac{3}{1}\times 0.0925=0.2775$

molarity of Cl⁻ :

$\tt \dfrac{0.2775}{0.45}=0.617~M$

7 0

3 years ago

. Determine the standard free energy change, ɔ(G p for the formation of S2−(aq) given that the ɔ(G p for Ag+(aq) and Ag2S(s) are

olga nikolaevna [1]

<u>Answer:</u> The standard free energy change of formation of $S^{2-}(aq.)$ is 92.094 kJ/mol

<u>Explanation:</u>

We are given:

$K_{sp}\text{ of }Ag_2S=8\times 10^{-51}$

Relation between standard Gibbs free energy and equilibrium constant follows:

$\Delta G^o=-RT\ln K$

where,

$\Delta G^o$ = standard Gibbs free energy = ?

R = Gas constant = $8.314J/K mol$

T = temperature = $25^oC=[273+25]K=298K$

K = equilibrium constant or solubility product = $8\times 10^{-51}$

Putting values in above equation, we get:

$\Delta G^o=-(8.314J/K.mol)\times 298K\times \ln (8\times 10^{-51})\\\\\Delta G^o=285793.9J/mol=285.794kJ$

For the given chemical equation:

$Ag_2S(s)\rightleftharpoons 2Ag^+(aq.)+S^{2-}(aq.)$

The equation used to calculate Gibbs free change is of a reaction is:

$\Delta G^o_{rxn}=\sum [n\times \Delta G^o_f_{(product)}]-\sum [n\times \Delta G^o_f_{(reactant)}]$

The equation for the Gibbs free energy change of the above reaction is:

$\Delta G^o_{rxn}=[(2\times \Delta G^o_f_{(Ag^+(aq.))})+(1\times \Delta G^o_f_{(S^{2-}(aq.))})]-[(1\times \Delta G^o_f_{(Ag_2S(s))})]$

We are given:

$\Delta G^o_f_{(Ag_2S(s))}=-39.5kJ/mol\\\Delta G^o_f_{(Ag^+(aq.))}=77.1kJ/mol\\\Delta G^o=285.794kJ$

Putting values in above equation, we get:

$285.794=[(2\times 77.1)+(1\times \Delta G^o_f_{(S^{2-}(aq.))})]-[(1\times (-39.5))]\\\\\Delta G^o_f_{(S^{2-}(aq.))=92.094J/mol$

Hence, the standard free energy change of formation of $S^{2-}(aq.)$ is 92.094 kJ/mol

8 0

3 years ago

Are usually solid shiny and conductive object

crimeas [40]

If the solid is a metal, yes. Most solids on the periodic table are metals

8 0

4 years ago

Classify these substances? More than one answer may apply in each case.

dalvyx [7]

Answer:

N2 element, pure substance

O2 element, pure substance

N2O Compound, pure substance

Air (mostly N2 and O2 ) homogeneous mixture

Explanation:

N2, Nitrogen is known as the chemical element that is characterized by having atomic number 7 and that is symbolized by the letter N, in its molecular version, it is recognized as N2.

O2, Oxygen is the chemical element of atomic number 8, this molecular form is composed of two atoms of this element.

A chemical element is a type of matter, consisting of atoms of the same class.

N2O, Nitrous oxide is formed by the union of two molecules of nitrogen and one of oxygen, which is considered a chemical compound since it is a substance formed by the chemical combination of two different elements of the periodic table.

A pure substance is one that cannot change state or divide into other substances, except for a chemical reaction.

Air (mostly N2 and O2 ), it is a homogeneous mixture of gases that constitutes the earth's atmosphere. A homogeneous mixture is a type of mixture in which its components are not distinguished and in which the composition is uniform and each part of the solution has the same properties.

3 0

3 years ago

The pH of a solution is 3.81. What is the OH concentration in the solution?

disa [49]

Answer:

6.46 × 10⁻¹¹ M

Explanation:

Step 1: Given data

pH of the solution: 3.81

Step 2: Calculate the pOH of the solution

We will use the following expression.

pH + pOH = 14.00

pOH = 14.00 - pH = 14.00 - 3.81 = 10.19

Step 3: Calculate the concentration of OH⁻ ions

We will use the definition of pOH.

pOH = -log [OH⁻]

[OH⁻] = antilog -pOH = antilog -10.19 = 6.46 × 10⁻¹¹ M

3 0

3 years ago