Formula Used
For titration, hydrogen tartrate reacts with hydroxide in a 1:1 ratio. Moles KHT in the titrated sample equal MNaOH × VNaOH. Solubility equals moles divided by sample liters, then multiplied by the dilution factor.
For equilibrium, KHT dissolves as KHT(s) ⇌ K+ + HT-. The equation is Ksp = ([K+] + s)([HT-] + s). In pure water, s = √Ksp.
The temperature option uses ln(K2/K1) = -ΔH/R × (1/T2 - 1/T1). Use it only when a trusted enthalpy value is available.
How to Use This Calculator
Select titration mode when you have a saturated KHT sample and NaOH endpoint data. Enter sample volume, base molarity, base volume, and any dilution factor.
Select equilibrium mode when you know Ksp and want solubility under common ion conditions. Enter the reference Ksp, temperature settings, and added potassium or hydrogen tartrate levels.
Press Calculate to view the result above the form. Use CSV for spreadsheet work. Use PDF for a simple report record.
Example Data Table
| Case |
Method |
Inputs |
Expected Use |
| Lab titration |
Titration |
20.00 mL sample, 0.0500 M NaOH, 12.10 mL titre |
Find measured saturated solubility |
| Pure water check |
Equilibrium |
Ksp = 3.8E-4, no common ions |
Estimate solubility from Ksp |
| Common ion case |
Equilibrium |
Ksp = 3.8E-4, K+ = 0.010 M, HT- = 0 M |
Show reduced solubility |
About KHT Solubility
KHT solubility is often measured in a saturated potassium hydrogen tartrate solution. The solid dissolves until the dissolved potassium and hydrogen tartrate ions reach equilibrium. This calculator helps you estimate that point from a titration result or from a solubility product setup. It is useful for chemistry reports, quality checks, and classroom exercises.
Titration Method
The titration method uses the neutralization between hydrogen tartrate and sodium hydroxide. One mole of base reacts with one mole of dissolved hydrogen tartrate. The measured base volume therefore gives the moles of KHT in the sample. The tool converts that amount into molarity, grams per liter, and total mass in the selected solution volume.
Equilibrium Method
The equilibrium method starts with Ksp. In pure water, Ksp equals s squared, so solubility is the square root of Ksp. With common ions, the calculator solves a quadratic equation. Added potassium or hydrogen tartrate lowers the amount of new solid that can dissolve. This is the common ion effect.
Temperature Adjustment
Temperature can also be considered. The optional van’t Hoff correction adjusts Ksp from a reference temperature. Enter an enthalpy value only when your lab source provides one. If you leave it as zero, the calculator uses the entered Ksp without correction.
Saturation Review
The saturation index compares the ionic product with Ksp. A value below one suggests more solid can dissolve. A value near one suggests equilibrium. A value above one suggests a supersaturated or precipitating condition. This quick flag is helpful when checking whether the numbers are physically sensible.
Unit Care
Use careful units. Volumes are entered in milliliters. Molarities are entered in moles per liter. The molar mass used here is 188.18 grams per mole. You can edit the default Ksp, reference temperature, common ion levels, and dilution factor to match your lab manual.
Reports
The CSV download is best for spreadsheets. The report download is useful for records or attachments. Always compare calculated values with observed crystals, temperature control, and instrument limits before drawing final conclusions. For stronger review, run both modes when data is available. Titration results show what the sample contained. Equilibrium results show what the model predicts. Large differences may reveal dilution errors, endpoint overshoot, contamination, or a Ksp value copied for another temperature. Record each assumption beside the final value.
FAQs
What is KHT?
KHT is potassium hydrogen tartrate. It is also called potassium bitartrate. In water, it forms potassium ions and hydrogen tartrate ions.
Which method should I use?
Use titration mode for lab endpoint data. Use equilibrium mode when you know Ksp and want to model temperature or common ion effects.
Why does the calculator use a 1:1 titration ratio?
Hydrogen tartrate donates one acidic proton to hydroxide. Therefore, one mole of NaOH neutralizes one mole of dissolved hydrogen tartrate.
What does common ion concentration mean?
It means potassium or hydrogen tartrate already present before more KHT dissolves. These ions usually reduce additional KHT solubility.
Can I change the Ksp value?
Yes. The default is only a working value. Replace it with the value required by your lab manual, textbook, or measured condition.
What does saturation index show?
It compares the starting ionic product with Ksp. Values below one suggest unsaturation. Values above one suggest supersaturation or precipitation risk.
Why is temperature included?
Solubility can change with temperature. The optional correction estimates a new Ksp when a valid dissolution enthalpy is supplied.
Is the PDF a detailed lab report?
No. It is a compact calculation record. Add your method notes, observations, uncertainty, and instructor requirements separately.