Concept explainers
9 Answer true or false.
(a) Matter is divided into elements and pure substances.
(b) Matter is anything that has mass and volume (occupies space).
(C) A mixture is composed of two or more pure substances.
(d) An element is a pure substance.
(e) A heterogeneous mixture can be separated into pure substances, but a homogeneous mixture cannot.
(f) A compound consists of elements combined in a fixed ratio.
(g) A compound is a pure substance.
(h) All matter has mass.
(I) All of the 118 known elements occur naturally on Earth.
(j) The first six elements in the Periodic Table are the most important for human life.
(k) The combining ratio of a compound tells you how many atoms of each element are combined in the compound.
(I) The combining ratio of 1:2 in the compound CO2 tells you that this compound is formed by the combination of one gram of carbon with two grams of oxygen.
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Chapter 2 Solutions
Introduction To General, Organic, And Biochemistry
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- World of Chemistry, 3rd editionChemistryISBN:9781133109655Author:Steven S. Zumdahl, Susan L. Zumdahl, Donald J. DeCostePublisher:Brooks / Cole / Cengage Learning