(a)
Interpretation:
The heat is absorbed or released when
Concept Introduction:
Endothermic Reactions:
The endothermic process is a term that describes a reaction where the system absorbs the energy from its surrounding in the form of heat. Few examples of endothermic process is photosynthesis, evaporating liquids, melting ice.
Exothermic reaction:
The exothermic reaction is the opposite of an endothermic reaction. It releases energy by light or heat to its surrounding. Few examples are neutralization, burning a substance, reactions of fuels, deposition of dry ice, respiration.
(b)
Interpretation:
The heat is absorbed or released when freezing of
Concept Introduction:
Refer to part (a).
(c)
Interpretation:
The heat is absorbed or released when condensing
Concept Introduction:
Refer to part (a).
(d)
Interpretation:
The heat is absorbed or released when vaporizing
Concept Introduction:
Refer to part (a).
Want to see the full answer?
Check out a sample textbook solutionChapter 4 Solutions
Principles of General Organic & Biological Chemistry
- sUse information from Figure 15.24 to calculate howmuch heat is required to vaporize 4.33 mol of waterat 100°C.arrow_forwardRefer to Figure 11.12 to answer these questions: (a) You heat some water to 60 C in a lightweight plastic bottle and seal the top very tightly so gas cannot enter or leave the carton. What happens when the water cools? (b) If you put a few drops of liquid diethyl ether on your hand, does it evaporate completely or remain a liquid? Figure 11.12 Vapor pressure curves for diethyl ether [(C2H3)2O], ethanol (C2H5OH), and water. Each curve represents conditions of T and P of which the two phases, liquid and vapor, are in equilibrium. These compounds exist as liquids for temperatures and pressures to the left of the curve and as gases under conditions to the right of the curve. (See Appendix G for vapor pressures for water of various temperatures.)arrow_forwardThe amount of heat required to melt 2 lbs of ice is twice the amount of heat required to melt 1 lb of ice. Is this observation a macroscopic or microscopic description of chemical behavior? Explain your answer.arrow_forward
- which of the following substances would have the least amount of heat of formation A. Gaseous ammonia B. Liquid water C. Solid carbon dioxide D. Soilid carbon (or graphite)arrow_forwardSolid iodine crystals left on a counter top will disappear over a short period of time without making a liquid "puddle". This is an example of a. sublimation b. condensation c. an exothermic process d. vapor pressurearrow_forwardIt is an attractive forces between polar molecules. 7. a Dipole-dipole b. Dispersion 8. Why the hydrogen bond is considered a "special" dipole-dipole interaction? It is polar C. Ion-dipole d. Intermolecular Because of the similarity in electronegativity d. Bonded to a very electron negative atom such as N, F and O C. a. b. It has covalent bonds 9. These intermolecular forces as a group are referred to as a. Intermolecular forces C. Solid forces b. London forces d. Van der Waals forcesarrow_forward
- When a liquid is freezing, a. its temperature decreases constantly b. the kinetic energy of its molecules increases. c. liquid and solid coexist d. its temperature decreases further after no more liquids remainarrow_forwardWhen 50 g of ethanol is heated from T1 below its freezing point to a temperature T2 above its freezing point, it absorbs 523 kJ of heat. If the same sample is cooled back from T2 until it freezes and is cooled back to T1, which of the following is true? a. The sample releases more than 523 kJ of heat to its surroundings. b. The sample releases less than 523 kJ of heat to its surroundings. c. The sample releases 523 kJ to its surroundings. d. It is impossible to know without the heat of fusion of ethanol.arrow_forwardWhat is the difference between a chemical and physical change? What is the difference between an intermolecular force and an intramolecular force? Explain why it takes more energy to break an intramolecular force than it does an intermolecular force. Define viscosity. Describe what surface tension is and how you know that water has a higher surface tension than alcohol. If a substance has a high viscosity, then it has strong intermolecular forces. For example, in the investigation we did, we found that room-temperature corn syrup had stronger intermolecular forces/higher viscosity than the hot corn syrup because it took longer for it to pour out of the beaker. Describe cohesion and adhesion and how they relate to your everyday life. Substances with high boiling, melting, and freezing points have stronger intermolecular forces. Four types of intermolecular forces: dispersion forces, hydrogen bonds (H-O, H-F, H-N), ion-dipole, dipole-dipole Which intermolecular force exists…arrow_forward
- You are tasked to determine the amount of energy required for a block of ice to become water vapor. What of the following information do you need to know in order to be able to complete this task. Select all that applies. A. Density of liquid water B. heat of fusion for water C. Heat of vaporization for water D. density of water vapor E. Density of ice F. initial temperature of the ice G. Temperature at which ice melts H. final temperature of water vapor I. temperature at which water boils J. mass of ice K. specific heat of waterarrow_forwardWhich of these properties of water is responsible for the increase in density of water upon melting? a. Surface tension b. The open-cage structure of ice and water c. High heat of vaporization d. London forcesarrow_forward7. Calculate the heat needed at 0°C to make each of the following changes of state. Indicate whether heat was absorbed or released. a. calories to freeze 35 g of water. b. calories to freeze 250 g of water. c. kilocalories to melt 140 g of ice. that cools from 110°C to -10°C. Indicatearrow_forward
- Chemistry: Matter and ChangeChemistryISBN:9780078746376Author:Dinah Zike, Laurel Dingrando, Nicholas Hainen, Cheryl WistromPublisher:Glencoe/McGraw-Hill School Pub CoWorld of Chemistry, 3rd editionChemistryISBN:9781133109655Author:Steven S. Zumdahl, Susan L. Zumdahl, Donald J. DeCostePublisher:Brooks / Cole / Cengage Learning
- Chemistry by OpenStax (2015-05-04)ChemistryISBN:9781938168390Author:Klaus Theopold, Richard H Langley, Paul Flowers, William R. Robinson, Mark BlaserPublisher:OpenStaxChemistry: The Molecular ScienceChemistryISBN:9781285199047Author:John W. Moore, Conrad L. StanitskiPublisher:Cengage LearningChemistry & Chemical ReactivityChemistryISBN:9781337399074Author:John C. Kotz, Paul M. Treichel, John Townsend, David TreichelPublisher:Cengage Learning