Solute Potential Calculator – Loan calculator

Solute Potential (Ψs) Calculator

Ionization Constant (i) (e.g., 1.0 for Sucrose, 2.0 for NaCl)

Molar Concentration (C) Moles per liter (M)

Temperature (°C) Degrees Celsius

Solute Potential (Ψ_s)

Understanding Solute Potential

Solute potential (Ψ_s), also known as osmotic potential, is a critical component of total water potential in plant biology and environmental science. It represents the effect of dissolved solutes on water potential. Pure water has a solute potential of zero. As solutes are added, the concentration of free water molecules decreases, causing the solute potential to become more negative.

The Solute Potential Formula

The calculator uses the Van 't Hoff equation to determine solute potential:

Ψ_s = -iCRT

i (Ionization Constant): The number of particles the molecule dissociates into in water. For instance, sucrose does not dissociate (i = 1), while NaCl dissociates into Na+ and Cl- (i = 2).
C (Molar Concentration): The concentration of the solute in moles per liter (Molarity).
R (Pressure Constant): A universal constant equal to 0.0831 liter bars / mole K.
T (Temperature): The absolute temperature in Kelvin (Kelvin = °C + 273).

Why is it Negative?

Solute potential is always zero or negative. Because solutes bind with water molecules, they reduce the potential energy of the water in a solution compared to pure water. This negative value explains why water moves via osmosis from areas of high water potential (low solute concentration) to areas of low water potential (high solute concentration).

Practical Example

Suppose you have a 0.3M sucrose solution at 25°C. To find the solute potential:

i: 1.0 (Sucrose)
C: 0.3 M
R: 0.0831
T: 25 + 273 = 298 K
Calculation: -(1.0) * (0.3) * (0.0831) * (298) = -7.43 bars

The resulting solute potential is -7.43 bars, indicating that the presence of the sucrose has significantly lowered the water potential of the solution.

function calculateSolutePotential() { var i = parseFloat(document.getElementById("ionizationConstant").value); var C = parseFloat(document.getElementById("molarConcentration").value); var tempC = parseFloat(document.getElementById("temperatureCelsius").value); var R = 0.0831; var resultArea = document.getElementById("resultArea"); var potentialValue = document.getElementById("potentialValue"); var breakdown = document.getElementById("calculationBreakdown"); if (isNaN(i) || isNaN(C) || isNaN(tempC)) { alert("Please enter valid numerical values for all fields."); return; } // Convert Celsius to Kelvin var T = tempC + 273; // Formula: Ψs = -iCRT var solutePotential = -1 * i * C * R * T; // Display result resultArea.style.display = "block"; resultArea.style.backgroundColor = "#fff5f5"; resultArea.style.border = "1px solid #feb2b2″; potentialValue.innerHTML = solutePotential.toFixed(2) + " bars"; breakdown.innerHTML = "Calculation: -(" + i + ") × (" + C + " M) × (0.0831) × (" + T + " K) = " + solutePotential.toFixed(4) + " bars"; }