GATE ChemE Calculator

Free Antoine equation calculator with step-by-step solutions — aligned with GATE 2025 Chemical Engineering paper.

Antoine Equation Calculator

log₁₀(P*) = A − B/(C+T)  ·  GATE CH exam prep

Valid range: 26–104°C

Antoine Constants — log₁₀(P/mmHg) = A − B/(C + T°C)

Benzene (26–104°C)

A = 6.90565

B = 1211.033

C = 220.79

Water (1–100°C)

A = 8.07131

B = 1730.63

C = 233.426

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Q47Antoine Equation★ Antoine2m · Psychrometry

Moist air has an absolute humidity of 0.02 kg moisture/kg dry air at 1 bar. MW_water = 18, MW_air = 29. Using the Antoine equation for water, find the dew temperature.

Answer: ≈ 26°C (299 K)T = B/(A − log₁₀P) − C
Q15Phase Rule1m · Thermodynamics

Find the number of independent intensive variables needed to describe a ternary mixture at vapour–liquid–liquid equilibrium (VLLE: 1 vapour + 2 liquid phases).

Answer: F = 2F = C − P + 2
Q40Adsorption2m · Mass Transfer

500 mg adsorbent added to 100 mL of 100 mg/L phenol solution. Residual concentration after 5 h = 30 mg/L. Find phenol adsorbed per gram of adsorbent.

Answer: 14 mg/gq = (C₀−Cf)·V / m_ads
Q51LMTD2m · Heat Transfer

Water (70 kg/min) heated from 25°C to 65°C in counter-flow HX. Hot oil: 110°C in, 65°C out. U = 300 W/(m²·K). Find heat exchanger area.

Answer: ≈ 15.4 m²A = Q / (U × LMTD)
Q65Drying Time2m · Drying Operations

100 kg wet solid, initial moisture X₁=0.30, final X₂=0.02, critical Xc=0.10, equilibrium Xe=0.01 (kg/kg dry). Rc=10 kg/h·m², area=5 m². Find total drying time.

Answer: ≈ 0.9 ht = Ms(X₁−Xc)/(Rc·A) + Ms(Xc−Xe)ln[…]/(Rc·A)
Q43Hagen-Poiseuille2m · Fluid Mechanics

For laminar flow in a cylindrical pipe at constant volumetric flow rate, verify how pressure drop ΔP changes with viscosity, pipe length, and diameter.

Answer: ΔP ∝ μ (TRUE), ΔP ∝ L (TRUE), ΔP ↓ with diameter (C is FALSE)ΔP = 128μLQ / (πd⁴)
Q26Cost Scaling1m · Plant Economics

Capital cost (CC) of equipment varies with capacity (S) as CC ∝ S^β. The rule-of-thumb value of β is __ (six-tenths rule). Calculate new cost when capacity changes.

Answer: β = 0.6CC₂ = CC₁ × (S₂/S₁)^0.6

GATE ChemE Calculator — Free exam prep tool

Antoine constants from Perry's Chemical Engineers' Handbook