Ch.1 - Matter, Measurement & Problem Solving

Tro - Chemistry: A Molecular Approach 6th Edition

Tro6th EditionChemistry: A Molecular ApproachISBN: 9780137832217Not the one you use?Change textbook

Tro 6th Edition

Ch.1 - Matter, Measurement & Problem Solving

Problem 49

Chapter 1, Problem 49

Based on the molecular diagram, classify each change as physical or chemical.

Verified step by step guidance

Observe the first molecular diagram: the blue molecules are spreading apart.

Identify that the blue molecules remain the same substance before and after the change.

Classify this change as a physical change because the molecules are simply moving apart without altering their chemical structure.

Observe the second molecular diagram: the blue and green molecules are rearranging.

Identify that new substances are formed as the blue and green molecules combine in different ways, indicating a chemical change.

Verified video answer for a similar problem:

This video solution was recommended by our tutors as helpful for the problem above.

Video duration:

Was this helpful?

Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Physical Change

A physical change involves a change in the state or appearance of a substance without altering its chemical composition. Examples include changes in state (solid to liquid), shape, or size. In the provided molecular diagram, the blue molecules spreading apart represent a physical change, as their identity remains unchanged despite the increase in distance between them.

Chemical Change

A chemical change results in the formation of one or more new substances with different chemical properties. This process often involves the breaking and forming of chemical bonds. The second molecular diagram illustrates a chemical change, where blue and green molecules rearrange, indicating that new substances are formed through the interaction of different types of molecules.

Molecular Representation

Molecular representation visually depicts the arrangement and interaction of molecules during physical and chemical changes. Understanding these diagrams helps in identifying the nature of the change occurring. The diagrams in the question serve as a tool to differentiate between physical changes, where molecules merely spread apart, and chemical changes, where molecular rearrangement occurs, leading to new substances.

Recommended video:

Guided course

02:38

Molecular Polarity

Related Practice

Textbook Question

The warmest temperature ever measured in the United States is 134 °F, recorded on July 10, 1913, in Death Valley, California. Convert that temperature to °C and K.

1356

views

Textbook Question

Use prefix multipliers to express each measurement without exponents. a. 3.4x10^-16m

Textbook Question

Classify each of the listed properties of ozone (a pollutant in the lower atmosphere but part of a protective shield against UV light in the upper atmosphere) as physical or chemical. a. bluish color b. pungent odor c. very reactive d. decomposes on exposure to ultraviolet light e. gas at room temperature

1085

views

Textbook Question

Classify each property as physical or chemical. a. the boiling point of ethyl alcohol b. the temperature at which dry ice evaporates c. the tendency of iron to rust d. the color of gold

622

views

Textbook Question

Convert each temperature. a. 32 °F to °C (temperature at which water freezes) b. 77 K to °F (temperature of liquid nitrogen) c. -109 °F to °C (temperature of dry ice) d. 98.6 °F to K (body temperature)

644

views

Textbook Question

Classify each change as physical or chemical. a. Natural gas burns in a stove. b. The liquid propane in a gas grill evaporates because the valve was left open. c. The liquid propane in a gas grill burns in a flame. d. A bicycle frame rusts on repeated exposure to air and water.

863

views