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Endothermic & Exothermic Reactions Solutions Library

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Endothermic & Exothermic Reactions

Q. What does positive ΔH tell about a reaction?

Solved • Mar 30, 2021

Endothermic & Exothermic Reactions

Q. Which of the following is true of melting ice at temperatures above 0°C?a. It is not spontaneous.b, It is not favorable.c. It is endothermic. 

Solved • Mar 30, 2021

Endothermic & Exothermic Reactions

Q. Given the balanced equation representing a reaction: H2 → H + H What occurs during this reaction? 1. Energy is absorbed as bonds are formed. 2. Ene...

Solved • Mar 23, 2021

Endothermic & Exothermic Reactions

Q. How should the baking of a pizza be categorized?a. as an exothermic process because the dough releases heatb. as an endothermic process because the...

Solved • Mar 22, 2021

Endothermic & Exothermic Reactions

Q. Which describes the enthalpy change associated with an endothermic reaction?a. It is negative because the enthalpy of the products is greater than ...

Solved • Mar 22, 2021

Endothermic & Exothermic Reactions

Q. Complete the following sentences about endothermic and exothermic changes.Exothermic changes: the system _ the surroundings. The heat _____ by the ...

Solved • Feb 9, 2021

Endothermic & Exothermic Reactions

Q. The temperature was then adjusted. When the equilibrium reaction was cooled (temperature was decreased), the equilibrium color changed to orange. O...

Solved • Jan 26, 2021

Endothermic & Exothermic Reactions

Q. What is the basic difference between exergonic and endergonic reactions?

Solved • Nov 17, 2020

Endothermic & Exothermic Reactions

Q. Assuming constant pressure, rank these reactions from most energy released by the system to most energy absorbed by the system, based on the follow...

Solved • Jul 2, 2020

Endothermic & Exothermic Reactions

Q. Watch the video of the thermite reaction, and then choose which of the following statements are correct for the thermite reaction.Check all that ap...

Solved • Jul 2, 2020

Endothermic & Exothermic Reactions

Q. Classify the following by the sign of ΔE for the system.Drag the appropriate items to their respective bins. If no definitive classification can be...

Solved • Jul 2, 2020

Endothermic & Exothermic Reactions

Q. In the PhET simulation window, click on the Intro tab and check the “Energy Symbols” box in the upper right. Perform the described tasks and fill i...

Solved • Jul 1, 2020

Endothermic & Exothermic Reactions

Q. Determine whether each process is exothermic or endothermic and indicate the sign of ΔΗ. a. dry ice evaporating b. a sparkler burning c. the reacti...

Solved • Jun 16, 2020

Endothermic & Exothermic Reactions

Q. An exothermic reaction causes the surroundings to A. warm up. B. become acidic. C. expand. D. decrease its temperature.E. release CO2.

Solved • Jun 16, 2020

Endothermic & Exothermic Reactions

Q. Water being turned into ice cubes in a freezer is an example of ___________ (endothermic or exothermic) process, and ∆H will be ___________. (posit...

Solved • May 1, 2020

Endothermic & Exothermic Reactions

Q. Based on relative bond strengths, classify these reactions as endothermic (energy absorbed) or exothermic (energy released ).

Solved • May 1, 2020

Endothermic & Exothermic Reactions

Q. 4Al(s) + 3 O2(g)→2Al2O3(s) q=-3351kJ is ____ and therefore heat is ______ by the reaction.

Solved • Apr 30, 2020

Endothermic & Exothermic Reactions

Q. The reaction between hydrogen and oxygen to form water is highly exothermic. Which statement is true of the energies of the bonds that break and fo...

Solved • Apr 20, 2020

Endothermic & Exothermic Reactions

Q. For a reaction to be endothermic, which of the following relationships is valid?a)  The energy required to break bonds is greater than the energy i...

Solved • Apr 14, 2020

Endothermic & Exothermic Reactions

Q. Based on their descriptions, classify these chemical changes as endothermic or exothermic.-A chemical change takes place in a container, making it ...

Solved • Mar 20, 2020

Endothermic & Exothermic Reactions

Q. Determine the enthalpy of solution for a solid with ΔH values as described in each scenario. Drag the appropriate items to their respective bins.

Solved • Mar 12, 2020

Endothermic & Exothermic Reactions

Q. A chemical reaction absorbs heat from the surroundings. Therefore it is _________ and has a ________ value of ΔH.A. endothermic, negative B. endoth...

Solved • Oct 3, 2019

Endothermic & Exothermic Reactions

Q. Which one of the following is an endothermic process?A) ice meltingB) water freezingC) boiling soupD) Hydrochloric acid and barium hydroxide are mi...

Solved • Sep 24, 2019

Endothermic & Exothermic Reactions

Q. Which of these physical changes would require the liberation of energy, exothermic?a. melting pointb. boiling pointc. condensation of steam to form...

Solved • Aug 30, 2019

Endothermic & Exothermic Reactions

Q. Is deposition endothermic or exothermic?

Solved • Aug 25, 2019

Endothermic & Exothermic Reactions

Q. Why is melting ice an endothermic reaction?

Solved • Aug 7, 2019

Endothermic & Exothermic Reactions

Q. Based on their descriptions, classify these chemical changes as endothermic or exothermic.

Solved • Aug 2, 2019

Endothermic & Exothermic Reactions

Q. 5.81Without doing any calculations, predict the sign of ΔH for each of the following reactions:(b) 2 H(g) → H2(g)

Solved • Jan 23, 2019

Endothermic & Exothermic Reactions

Q. A standard air conditioner involves a refrigerant that is typically now a fluorinated hydrocarbon, such as CH2F2. An air-conditioner refrigerant ha...

Solved • Jan 3, 2019

Endothermic & Exothermic Reactions

Q. What is the sign of ΔH for the process depicted in the figure above?

Solved • Jan 3, 2019

Endothermic & Exothermic Reactions

Q. Consider the vaporization of liquid water to steam at a pressure of 1 atm.Is this process endothermic or exothermic?

Solved • Jan 3, 2019

Endothermic & Exothermic Reactions

Q. When ammonium chloride (NH4Cl) is dissolved in water, the solution becomes colder. Is the dissolution of ammonium chloride endothermic or exothermic?

Solved • Dec 3, 2018

Endothermic & Exothermic Reactions

Q. Classify each process as endothermic or exothermic.a. gasoline burning in an engineb. steam condensing on a mirrorc. water boiling in a pot

Solved • Nov 12, 2018

Endothermic & Exothermic Reactions

Q. What is the sign of ΔH for each process.a. gasoline burning in an engineb. steam condensing on a mirrorc. water boiling in a pot

Solved • Nov 12, 2018

Endothermic & Exothermic Reactions

Q. You may want to reference (Pages 267 - 270) Section 6.6 while completing this problem.Identify each process as endothermic or exothermic and indica...

Solved • Nov 12, 2018

Endothermic & Exothermic Reactions

Q. Identify each process as endothermic or exothermic and indicate the sign of ΔH.(a) an ice cube melting(b) nail polish remover quickly evaporating a...

Solved • Nov 12, 2018

Endothermic & Exothermic Reactions

Q. Which process is endothermic?a) the evaporation of water from the skinb) the burning of candle waxc) the oxidation of iron in a chemical hand warme...

Solved • Nov 12, 2018

Endothermic & Exothermic Reactions

Q. In an exothermic reaction, the reactants lose energy and the reaction feels hot to the touch. Explain why the reaction feels hot even though the re...

Solved • Nov 12, 2018

Endothermic & Exothermic Reactions

Q. Indicate the sign of ΔH for the following processes.a. natural gas burning on a stoveb. isopropyl alcohol evaporating from skinc. water condensing ...

Solved • Nov 12, 2018

Endothermic & Exothermic Reactions

Q. Determine whether each of the following is exothermic or endothermic.dry ice evaporating,a sparkler burning, andthe reaction that occurs in a chemi...

Solved • Nov 12, 2018

Endothermic & Exothermic Reactions

Q. Indicate the sign of ΔH for the following processes.dry ice evaporating,a sparkler burning, andthe reaction that occurs in a chemical cold pack oft...

Solved • Nov 12, 2018

Endothermic & Exothermic Reactions

Q. Determine whether each of the following is exothermic or endothermic.a. natural gas burning on a stoveb. isopropyl alcohol evaporating from skinc. ...

Solved • Nov 12, 2018

Endothermic & Exothermic Reactions

Q. Explain the difference between an exothermic and an endothermic reaction.

Solved • Nov 12, 2018

Endothermic & Exothermic Reactions

Q. Explain the difference between an exothermic and an endothermic reaction. Give the sign of ΔH for each type of reaction.

Solved • Nov 12, 2018

Endothermic & Exothermic Reactions

Q. From a molecular viewpoint, where does the energy emitted in an exothermic chemical reaction come from?

Solved • Nov 12, 2018

Endothermic & Exothermic Reactions

Q. Why does the reaction mixture undergo an increase in temperature even though energy is emitted?

Solved • Nov 12, 2018

Endothermic & Exothermic Reactions

Q. From a molecular viewpoint, where does the energy absorbed in an endothermic chemical reaction go?

Solved • Nov 12, 2018

Endothermic & Exothermic Reactions

Q. Why does the reaction mixture undergo a decrease in temperature even though energy is absorbed?

Solved • Nov 12, 2018

Endothermic & Exothermic Reactions

Q. If an endothermic reaction absorbs heat, then why does it feel cold to the touch?

Solved • Nov 12, 2018

Endothermic & Exothermic Reactions

Q. Explain the difference between endothermic reactions and exothermic reactions with respect to the bond energies of the bonds broken and formed.

Solved • Nov 12, 2018

Endothermic & Exothermic Reactions

Q. Specific heat of water.Is the process shown in the figure endothermic or exothermic?

Solved • Oct 31, 2018

Endothermic & Exothermic Reactions

Q. Without doing any calculations, predict the sign of ΔH for each of the following reactions:(a) NaCl(s) → Na+(g) + Cl-(g)

Solved • Oct 31, 2018

Endothermic & Exothermic Reactions

Q. Without doing any calculations, predict the sign of ΔH for each of the following reactions:(a) 2NO2(g) → N2O4(g)

Solved • Oct 31, 2018

Endothermic & Exothermic Reactions

Q. Imagine a container placed in a tub of water, as depicted in the accompanying diagram.If the contents of the container are the system and heat is a...

Solved • Oct 31, 2018

Endothermic & Exothermic Reactions

Q. Liquid propane in the tank, C3H8, vaporizes and mixes with air as it escapes through the nozzle. The combustion reaction of C3H8 and O2 produces a ...

Solved • Oct 31, 2018

Endothermic & Exothermic Reactions

Q. When a reaction occurs in a flask, you notice that the flask gets colder. What is the sign of ΔHDelta {H}?

Solved • Oct 31, 2018

Endothermic & Exothermic Reactions

Q. A chemical reaction that gives off heat to its surroundings is said to be ____________ and has a ____________ value of H.

Solved • Oct 31, 2018

Endothermic & Exothermic Reactions

Q. Consider the conversion of compound A into compound B : A  →  B. For both compounds A and B, ΔH˚f > 0. Suppose the overall reaction is exothermi...

Solved • Oct 31, 2018

Endothermic & Exothermic Reactions

Q. You may want to reference (Pages 172 - 176)Section 5.3 while completing this problem.Consider the following reaction: 2 CH3OH(g)  →  2CH4(g) + O2 (...

Solved • Oct 31, 2018

Endothermic & Exothermic Reactions

Q. You may want to reference(Pages 166 - 172)Section 5.2 while completing this problem.A 100.0-g bar of gold is heated from 25˚C to 50˚C during which ...

Solved • Oct 31, 2018

Endothermic & Exothermic Reactions

Q. Consider the following reaction:2Mg(s) + O2 (g) → 2MgO(s)  ΔH = - 1204 kJIs this reaction exothermic or endothermic?

Solved • Oct 31, 2018

Endothermic & Exothermic Reactions

Q. At one time, a common means of forming small quantities of oxygen gas in the laboratory was to heat KClO3: 2 KClO3(s) → 2 KCl(s) + 3 O2(g), ΔH = –8...

Solved • Oct 31, 2018

Endothermic & Exothermic Reactions

Q. The methane molecule, CH4, has the geometry shown in following figure. Imagine a hypothetical process in which the methane molecule is "expanded," ...

Solved • Oct 31, 2018

Endothermic & Exothermic Reactions

Q. For a given process at constant pressure, H is positive. Is the process endothermic or exothermic?

Solved • Oct 31, 2018

Endothermic & Exothermic Reactions

Q. In the cylinder diagrammed below , a chemical process occurs at constant temperature and pressure.Given that the process is endothermic, does the i...

Solved • Oct 31, 2018

Endothermic & Exothermic Reactions

Q. You may want to reference (Pages 177 - 178) Section 5.4 while completing this problem.Without referring to tables, predict which of the following h...

Solved • Oct 31, 2018

Endothermic & Exothermic Reactions

Q. Consider the combustion of liquid methanol, CH3 OH(l): CH3OH(l) + 3/2 O2(g) → CO2(g) + 2 H2O(l), ΔH = –726.5kJWhich is more likely to be thermodyna...

Solved • Oct 31, 2018

Endothermic & Exothermic Reactions

Q. Consider the combustion of liquid methanol, CH3 OH(l): CH3OH(l) + 3/2 O2(g) → CO2(g) + 2 H2O(l), ΔH = –726.5kJIf the reaction were written to produ...

Solved • Oct 31, 2018

Endothermic & Exothermic Reactions

Q. Consider the decomposition of liquid benzene, C6H6(l), to gaseous acetylene, C2H2(g): C6H6(l) → 3 C2H2(g), ΔH = +630 kJWhich is more likely to be t...

Solved • Oct 31, 2018

Endothermic & Exothermic Reactions

Q. Consider the decomposition of liquid benzene, C6H6(l), to gaseous acetylene, C2H2(g): C6H6(l) → 3 C2H2(g), ΔH = +630 kJIf C6H6(g) were consumed ins...

Solved • Oct 31, 2018

Endothermic & Exothermic Reactions

Q. Calculate ΔE and determine whether the process is endothermic or exothermic for the following cases:(b) A system releases 66.1 kJ of heat to its su...

Solved • Oct 31, 2018

Endothermic & Exothermic Reactions

Q. Determine whether the process is endothermic or exothermic.A system releases 856 kJ of heat to the surroundings and has 788 kJ of work done on it b...

Solved • Oct 31, 2018

Endothermic & Exothermic Reactions

Q. When H2(g) and O2(g) react to form H2O(l), heat is released to the surroundings. Consider the reverse reaction, namely, the formation of H2(g) and ...

Solved • Oct 31, 2018

Endothermic & Exothermic Reactions

Q. Consider the energy diagram shown in the figure .If there is no work associated with the process, is it exothermic or endothermic?

Solved • Oct 31, 2018

Endothermic & Exothermic Reactions

Q. The contents of the closed box in each of the illustrations  represent a system, and the arrows show the changes to the system during some process....

Solved • Oct 31, 2018

Endothermic & Exothermic Reactions

Q. Ethyl chloride (boiling point, 13 °C) is used as a local anesthetic. When the liquid is sprayed on the skin, it cools the skin enough to freeze and...

Solved • Oct 30, 2018

Endothermic & Exothermic Reactions

Q. Are the following processes exothermic or endothermic?a. the combustion of gasoline in a car engine

Solved • Oct 17, 2018

Endothermic & Exothermic Reactions

Q. Are the following processes exothermic or endothermic?d. F2 (g) → 2F (g)

Solved • Oct 17, 2018

Endothermic & Exothermic Reactions

Q. Are the following processes exothermic or endothermic?a. When solid KBr is dissolved in water, the solution gets colder.

Solved • Oct 17, 2018

Endothermic & Exothermic Reactions

Q. Are the following processes exothermic or endothermic?b. Natural gas (CH4) is burned in a furnace.

Solved • Oct 17, 2018

Endothermic & Exothermic Reactions

Q. One of the components of polluted air is NO. It is formed in the high-temperature environment of internal combustion engines by the following react...

Solved • Oct 17, 2018

Endothermic & Exothermic Reactions

Q. Which produces more heat, Os(s) + 2O2(g) ⟶ OsO4(s) or Os(s) + 2O2(g) ⟶ OsO4(g)? For the phase change OsO4(s) ⟶ OsO4(g),    ΔH = 56.4 kJ

Solved • Oct 16, 2018

Endothermic & Exothermic Reactions

Q. Both graphite and diamond burn.C(s, diamond) + O2(g) ⟶ CO2(g)For the conversion of graphite to diamond:C(s, graphite) → C(s, diamond)              ...

Solved • Oct 16, 2018

Endothermic & Exothermic Reactions

Q. Draw an enthalpy diagram for a general endothermic reaction; label the axis, reactants, products, and ΔH with its sign.

Solved • Oct 15, 2018

Endothermic & Exothermic Reactions

Q. When 2 moles of C2H6 (g) react with O2 (g) to form CO2 (g) and H2O (g) according to the following equation, 2.86 x 103 kJ of energy are evolved. 2C...

Solved • Jul 18, 2018

Endothermic & Exothermic Reactions

Q. Which of the following reactions are exothermic?

Solved • Mar 30, 2018

Endothermic & Exothermic Reactions

Q. Predict whether the following reactions will be exothermic or endothermic.a. N2(g) + 3H2(g) → 2NH3(g)b. S(g) + O2(g) → SO2(g)c. 2H2O(g) → 2H2(g) + ...

Solved • Mar 27, 2018

Endothermic & Exothermic Reactions

Q. The formation of CsCl from Cs(s) and Cl 2(g) involves the following steps. Which of these steps absorb energy and which release energy?a. Cs(s) → C...

Solved • Mar 26, 2018

Endothermic & Exothermic Reactions

Q. The reaction between hydrogen and oxygen to form water is highly exothermic. Which statement is true of the energies of the bonds that break and fo...

Solved • Mar 26, 2018

Endothermic & Exothermic Reactions

Q. Which of the following is true of an endothermic reaction?a. Strong bonds break and weak bonds form: this means that more energy is released than a...

Solved • Mar 22, 2018

Endothermic & Exothermic Reactions

Q. Which process is endothermic?a. The burning of candle wax.b. The combustion of natural gas in a stove.c. The formation of a chemical bond.d. The me...

Solved • Mar 20, 2018

Endothermic & Exothermic Reactions

Q. Which statement is FALSE?a. ΔErxn is a measure of heat.b. Endothermic has a positive ΔH.c. An exothermic reaction gives heat off to the surrounding...

Solved • Mar 20, 2018

Endothermic & Exothermic Reactions

Q. Given w = 0, an endothermic reaction has which of the following:a. +ΔH and +ΔEb. -ΔH and -ΔEc. +ΔH and -ΔEd. -ΔH and +ΔE

Solved • Mar 20, 2018

Endothermic & Exothermic Reactions

Q. Which of the following processes is exothermic?a. a candle flameb. the vaporization of waterc. melting of iced. the chemical reaction in a "cold pa...

Solved • Mar 20, 2018

Endothermic & Exothermic Reactions

Q. Sort the following reactions as either endothermic or exothermic. Explain your answer briefly.

Solved • Mar 20, 2018

Endothermic & Exothermic Reactions

Q. Which of the following statements are true?a. ΔH for an endothermic reaction is positive.b. ΔH for an exothermic reaction is positive.c. When energ...

Solved • Mar 20, 2018

Endothermic & Exothermic Reactions

Q. Classify each process as endothermic or exothermic. What is the sign of ΔH for each process? a. Gasoline burning in an engineb. Steam condensing on...

Solved • Mar 19, 2018

Endothermic & Exothermic Reactions

Q. Sort the following reactions as either endothermic or exothermic.a. making popcorn in a microwave oven b. a burning match c. the reaction inside a ...

Solved • Mar 16, 2018

Endothermic & Exothermic Reactions

Q. Classify each process as an endothermic or exothermic process.1. forming solute-solvent attractions2. breaking solute-solute attractions3. breaking...

Solved • Mar 16, 2018

Endothermic & Exothermic Reactions

Q. Predict whether the following reactions will be exothermic or endothermic.a. N2(g) + 3H2(g) → 2NH3b. S(g) + O2(g) → SO2(g)c. 2H2O(g) → 2H2(g) + O2(...

Solved • Mar 16, 2018