29 Answered Questions for the topic Enthalpy
Hess's Law of Heat Summation
Liquid hydrazine, N2H4(l), is a rocket fuel. It combusts in oxygen gas to form nitrogen gas and liquid water:N2H4(l) + O2(g) -> N2(g) + 2H2O(l)Use the following thermochemical equations to... more
How can I use standard entropies and heats of formation to calculate ΔGƒ° at a certain temperature (°C)?
Use standard entropies and heats of formation to calculate ΔGƒ° at 25°C for the following compounds:a) ammonium nitrate (s)b) chloroform, CHCl3(l)c) potassium chloride (s)
Enthalpy Change Given 3 Reactions & Their Enthalpy Changes
Use the enthalpy changes given in the data below to calculate the enthalpy change for this reaction:Ca(OH)2(s) → CaO(s) + H2O(g)Data: Reaction no. Reaction ΔrH° / kJ mol-1 at 298K, standard state... more
In gluconeogenesis, glucose can be produced by reaction of pyruvic acid and glycerol. Upon consideration of the simplified version of this reaction, as shown below, and making use of the data in... more
Enthalpy of reaction, thermochemical equations
How much energy is released when 0.40 mol C6H6(g) completely reacts with oxygen? 2C6H6(g) + 15O2(g) => 12CO2(g) + 6H2O(g) the answer is -1268 but i need help getting there
What are the answers to these Enthalpy questions? I need to check my them homework please
1.H2O(l) H2O(g)2.2 SO2 (g) + O2 (g) 2 SO3 (g)3.SO3 (g) + H2O(l) H2SO4 (l)4.2 HI(g) H2 (g) + I2 (s)5.4 NH3 (g) + 5 O2 (g) 4 NO(g) + 6 H2O(l)6.CH4 (g) + 2 O2 (g) CO2 (g) + 2 H2O(g)7.CH4 (g) + 2 O2... more
what is the standard enthalpy change for the reaction
Given the standard enthalpy changes for the following two reactions:(1) 2Ni(s) + O2(g)2NiO(s)...... ΔH° = -479.4 kJ(2) Ni(s) + Cl2(g)NiCl2(s)......ΔH° = -305.3 kJwhat is the standard enthalpy... more
the standard enthalpy of formation of ICl(g) is
A scientist measures the standard enthalpy change for the following reaction to be -25.6 kJ :I2(g) + Cl2(g)2ICl(g)Based on this value and the standard enthalpies of formation for the other... more
Using standard heats of formation, calculate the standard enthalpy change for the following reaction.
Using standard heats of formation, calculate the standard enthalpy change for the following reaction. Fe(s) + 2HCl(aq)FeCl2(s) + H2(g)
Are covalent bonds stronger than ionic bonds
The experimental lattice enthalpy of a compound gets more exothermic than the theoretical lattice enthalpy of the compound if it has more covalent characteristics.This is because theoretical... more
Why is the enthalpy of atomisation also the bond enthalpy?
My book says that the enthalpy of atomisation is the enthalpy change when one mole of its atoms in the gaseous state is formed from the element under standard conditions. eg. C(graphite)➙... more
Ionization energy doubt
What is negative and positive ionization enthalpy?
Calculating Enthalpy in a Calorimeter Experiment
When 25.0 mL of 1.0 M H2SO4 is added to 50.0mL of 1.0M of NaOH at 25.0 degrees C in a calorimeter, the temperature of the aqueous solution increases to 33.9 degrees C. Assuming that the specific... more
Determine delta H
In a coffee-cup calorimeter, 1 mol NaOH and 1 mol HCl initially at 22 oC (Celsius) are mixed in 100g of water to yield the following reaction:NaOH + HCl → Na+(aq) + Cl-(aq) + H2O(l)After mixing... more
Enthalpy problem need help asap
CH3OH (l) + 3/2 O2 (g) -> CO2 (g) + 2H2O (l) delta h = -726.5 kJ calculate the mass of methanol needed to create 6.90 x 10^4 J of heat
find the mass that was burned
C2H6 + O2→CO2 + H2O. The heat from this reaction vaporized 20 grams of water. What mass of C2H6 was burned?
find the final temperature
4 grams CaCl2 is dissolved in 40 grams of water at 1 degree C. Find the final temperature of the water.
chemistry enthalpy question
Consider an ionic compound, MX2, composed of generic metal M and generic, gaseous halogen X. The enthalpy of formation of MX2 is ΔHf° = –861 kJ/mol. The enthalpy of sublimation of M is ΔHsub =... more
Can you PLEASE help me with CHEM? Using bond energies to determine the enthalpy of reaction for the following reaction???
I am kind of confused with this, so if you could show your work so I understand how you get the answer, I would appreciate it more than you know!!!Use the Table of Bond Energy Terms (BE), to... more
Finding the standard enthalpy of a reaction using enthalpies of atom combination
Using the enthalpies of atom combination listed in the table to the right, calculate the standard enthalpy of the following reaction. Substance Enthalpy CH3OH(g) -2037.11 O2(g) ... more
Constant-pressure calorimeter, finding change in energy
In a constant-pressure calorimeter, 50.0 mL of 0.340 M Ba(OH)2 was added to 50.0 mL of 0.680 M HCl. The reaction caused the temperature of the solution to rise from 24.07 °C to 28.70 °C. If the... more
What is the standard enthalpy of combustion of maltodextrin?
Writing a lab about yeast metabolism and one metabolite we used was maltodextrin. I cannot find the standard enthalpy of combustion anywhere for this sugar but I can find it for the other sugars we... more
Calculate enthalpy change for a reaction?? PLEASE help????????
The enthalpy change for the following reaction is -483.6 kJ: 2H2 (g) + O2 (g) → 2H2O (g) Therefore, the enthalpy change for the following reaction is __________ kJ: 4H2 (g) + 2O2 (g) → 4H2O... more
Enthalpty stoichiometry problem?? PLEASE help??!!
The value of H for the reaction below is -72 kJ. _______kJ of heat are released when 1.0 mol of HBr is formed in this reaction. H2 (g) + Br2(g) => 2HBr (g) I tried to solve it.. 1.0 mol HBr (-72... more