Enthalpy Study guides, Class notes & Summaries

15 kg/s of air are compressed from 1 atm and 300K (enthalpy of 300.19 kJ/kg) to 2 atm and 900K (enthalpy of 732.93 kJ/kg). Heat transfer is negligible. The air compressor's power output is most nearly (A) 5.6 MW (B) 6.5 MW (C) 7.6 MW (D) 8.9 MW - Answer-B What is most nearly the weight in lbf if a 1.00lbm object in a gravitational field of 27.5ft/s^2? (A) 0.85lbf (B) 1.2lbf (C) 28lbf (D) 32lbf - Answer-A A rocket that has a mass of 4000 lbm travels at 27,000 ft/sec. What is mo...

A __________ ΔH corresponds to an __________ process. -zero, endothermic -positive, exothermic -negative, endothermic -zero, exothermic -positive, endothermic correct answer: positive, endothermic Which one of the following is NOT considered a fossil fuel? -natural gas -hydrogen -anthracite coal -petroleum -crude oil correct answer: hydrogen Which one of the following statements is FALSE? -The enthalpy change for a reaction is equal in magnitude, but opposite i...

BioChem 210 Module 2 Exam - Portage Learning 1. The pH of a solution of 0.0010 M NaOH is:: 11 (Kw=[H+][OH-] = 1.0 x 10-14; [H+][0.0010] = 1.0 x 10-14 [H+]=1.0 x 10-11; pH=-log[1.0 x 10- 11]=11) 2. Water is a unique molecule. Which of the following contributes to water's unique place in the chemical world?: All of the answers are correct 3. The bent shape of water is due to ______________.: The unshared electron pairs on the oxygen atom 4. Which diagrams correctly represent ...

Chem Exam: Types of Calculation Questions & Answers 100% Verified Calorimetry Calculations: 1. 2.50 kJ of energy changes the temperature of a sample of lead by 8.52 degrees C. What is the mass of the sample? - ANS-Q = mcΔT m=Qc/Δt m = 2500/0.13(8.52) = 2.3×103 g 2. 950.3 J of energy is removed from 28.5 g of water at 80.3 degrees C. What is the final temperature? - ANS-Q = mcΔT −950.3 = 28.5(4.18)(T2 − 80.3) T2 = −950.3/(28.5)(4.18) + 80.3 = 72.3O C 3. A 30.56 g sample...

IB chemistry HL Latest Version Graded A+ exothermic reaction heat is released by the system ΔΗ<0 endothermic reaction heat is absorbed by the system ΔΗ>0 standard enthalpy change of reaction(ΔΗ) the heat energy transferred under standard conditions (pressure-101.3 kPa, temperature- 298 K) combustion and neutralization are exothermic processes average bond enthalpy the energy required to break one mole of a certain type of bond in the gaseous state averaged acro...

Detailed notes on Unit 8 - Energetics I covering all the specification points, and allowed me to achieve an A* in chemistry. Covers enthalpy changes, thermochemical equations, Hess's law, Hess cycles, example calculations, standard enthalpy of formation, reaction, combustion, neutralisation and atomisation, bond enthalpy calculations with examples and enthalpy titrations.

IB Chemistry Topic 5 Latest Update Graded A+ Enthalpy The amount of heat released (exothermic) or absorbed (endothermic) during a chemical reaction (the energy needed for the reaction to occur) This can be lowered with the presence of a catalyst. Change in Enthalpy Hproducts -Hreactants Specific heat equation c= q in Joules (or Change in H)/mass(g)(change in temp) Specific heat of water 4.18 J/gdegreesC **NOTE: Usually in kJ Endothermic v. Exothermic Endothermic: Absorbing e...

CHEM 210 MODULE 3 EXAM QUESTIONS AND CORRECT ANSWERS, WITH COMPLETE SOLUTION 2024. What is meant by the term average bond enthalpy? (Average enthalpy change) when one mole of bonds of (gaseous covalent) bonds is broken The calculated value of ΔHc from this experiment is different from the value obtained from data books. Apart from heat loss, suggest two reasons for the difference. Assume that the calculation has been carried out correctly. incomplete combustion non-standard conditi...

A __________ ΔH corresponds to an __________ process. -zero, endothermic -positive, exothermic -negative, endothermic -zero, exothermic -positive, endothermic correct answerspositive, endothermic Which one of the following is NOT considered a fossil fuel? -natural gas -hydrogen -anthracite coal -petroleum -crude oil correct answershydrogen Which one of the following statements is FALSE? -The enthalpy change for a reaction is equal in magnitude, but opposite in si...

AQA CHEMISTRY A LEVEL WITH COMPLETE SOLUTIONS covalent bond - ANSWER-a shared pair of electrons between non-metal elements co-ordinate bond - ANSWER-a shared pair of electrons where both electrons are supplied by one atom repulsion in shapes of molecules - ANSWER-Lone pair-lone pair > lone pair-bonding pair > bonding pair-bonding pair electronegativity - ANSWER-the power of an atom to attract the pair of electrons in a covalent bond hess' law - ANSWER-Total enthalpy chang...