Concept explainers
(a)
Interpretation:
Whether the powder is an element or a compound is to be predicted.
Concept introduction:
Element is a purest form of substance that cannot be broken down using
Element as well as compound both has definite composition and properties.
(b)
Interpretation:
Whether the contents of the box are homogenous or heterogeneous is to be predicted.
Concept introduction:
A homogeneous mixture has the same proportions of its components throughout a given sample having uniform appearance. A heterogeneous mixture has components whose proportions vary throughout the sample and visibly different substances the appearance is not uniform throughout.
(c)
Interpretation:
Whether the contents of the box are either a pure substance or a mixture is to be predicted.
Concept introduction:
A mixture is defined as a substance made by combination of two or more different materials in such a way that no chemical reaction occurs. A mixture can usually be separated back into its original components by various chemical or physical methods.
A pure substance has constant physical and chemical properties and cannot be separated by any physical or chemical methods it does not have varying composition.
Want to see the full answer?
Check out a sample textbook solutionChapter 2 Solutions
Introductory Chemistry: An Active Learning Approach
- hat do the coefficients of a balanced chemical equation tell us about the proportions in which atoms and molecules react on an individual (microscopic) basis?arrow_forwardIs there a difference between a homogeneous mixture of hydrogen and oxygen in a 2:1 mole ratio and a sample of water vapor? Explain.arrow_forward3.68 Magnesium is lighter than other structural metals, so it is increasingly important in the design of more efficient vehicles. Mg2+ ions are present in seawater, and the metal is often prepared by "harvesting" these ions and converting them to Mg metal. The average magnesium content of the oceans is about 1270 g Mg2+ per ton of seawater, and the density of seawater is about 1.03 g/mL. What is the molarity of Mg2+ ions in seawater? The design for a concept car calls for 103 kg of magnesium per vehicle. How many gallons of seawater would be required to supply enough magnesium to build one of these ears?arrow_forward
- The present average concentration (mass percent) of magnesium ions in seawater is 0.13%. A chemistry textbook estimates that if 1.00 × 108 tons Mg were taken out of the sea each year, it would take one million years for the Mg concentration to drop to 0.12%. Do sufficient calculations to either verify or refute this statement. Assume that Earth is a sphere with a diameter of 8000 mi, 67% of which is covered by oceans to a depth of 1 mi, and that no Mg is washed back into the oceans at any time.arrow_forwardThere are five hydrocarbon compounds (compounds of C and II) that have the formula C6H14. (These are isomers; they differ in the way that C and H atoms are attached. Chapter 23) All are liquids at room temperature but have slightly different densities. (a) You have a pure sample of one of these hydrocarbons, and to identify it you decide to measure its density. You determine that a 5.0-mL sample (measured in a graduated cylinder) has a mass of 3.2745 g (measured on an analytical balance). Assume that the accuracy of the values for mass and volume is plus or minus one ( 1) in the last significant figure. What is the density of the liquid? (b) Can you identify the unknown hydrocarbon based on your experiment? (c) Can you eliminate any of the five possibilities based on the data? If so, which one(s)? (d) You need a more accurate volume measurement to solve this problem, and you redetermine the volume to be 4.93 mL Based on this new informationwhat is the unknown compound?arrow_forward3.107 As computer processor speeds increase, it is necessary for engineers to increase the number of circuit elements packed into a given area. Individual circuit elements are often connected using very small copper “wires” deposited directly onto the surface of the chip. In some processors, these copper interconnects are about 22 nm wide. How many copper atoms would be in a 1-mm length of such an interconnect, assuming a square cross section? (The density of copper is 8.96 g/cm3.)arrow_forward
- Chemistry & Chemical ReactivityChemistryISBN:9781337399074Author:John C. Kotz, Paul M. Treichel, John Townsend, David TreichelPublisher:Cengage LearningChemistry: The Molecular ScienceChemistryISBN:9781285199047Author:John W. Moore, Conrad L. StanitskiPublisher:Cengage LearningLiving By Chemistry: First Edition TextbookChemistryISBN:9781559539418Author:Angelica StacyPublisher:MAC HIGHER
- World of Chemistry, 3rd editionChemistryISBN:9781133109655Author:Steven S. Zumdahl, Susan L. Zumdahl, Donald J. DeCostePublisher:Brooks / Cole / Cengage LearningChemistry for Engineering StudentsChemistryISBN:9781337398909Author:Lawrence S. Brown, Tom HolmePublisher:Cengage LearningChemistry: Matter and ChangeChemistryISBN:9780078746376Author:Dinah Zike, Laurel Dingrando, Nicholas Hainen, Cheryl WistromPublisher:Glencoe/McGraw-Hill School Pub Co