Fe 3+ + SCN- --> FeSCN 2+
<span>.......Fe 3+.......SCN-.........FeSCN 2+ </span>
<span>I.......0.04..........0.001.............. </span>
<span>C........-x...............-x............. </span>
<span>E.....0.04-x.....0.001-x...........x </span>
<span>Keq = 203.4 = x / (0.04-x)(0.001-x) </span>
<span>203.4 = x / (x^2 - 0.041x + 4x10^-5) </span>
<span>203.4x^2 - 8.34x + 0.00094 = x </span>
<span>203.4x^2 - 9.34x + 0.00094 = 0 </span>
<span>x = -0.0001M or 0.0458M </span>
<span>therefore, according to the calculated Keq, all of the SCN- and Fe 3+ would be fully converted into FeSCN 2+</span>
Step

: To find the mass of a single washer, divide the total measured mass by the number of washers

. Step

: Convert kilograms to milligrams knowing

; thus

resulting in the final answer

.
The scenario that would lead to an endothermic ΔHsolution is when |ΔHsolute| > |ΔHhydration|. Explanation: A solution is characterized as a homogeneous mixture of two or more substances that can exist in gas, liquid, or solid forms. The enthalpy of solution may either be positive (indicating an endothermic reaction) or negative (indicating an exothermic reaction). Enthalpy represents the heat released or absorbed during the dissolution process at constant pressure. The initial step of this process involves separating the solute, which breaks all the intermolecular forces binding the solute together. This separation is an endothermic process, requiring energy to disrupt these interactions. Therefore, ΔH1 is positive. Consequently, for this situation to result in an endothermic reaction, the enthalpy of the solute must exceed the enthalpy of hydration.
Atoms have their protons and neutrons situated in the nucleus.
Electrons orbit in the outer shells, also known as orbitals.
Subatomic particles, comprising protons, neutrons, and electrons, reside within the atoms.