Answer the following question given this paragraph: Metallic character refers to the level of reactivity of a metal. Metals tend to lose electrons in chemical reactions, as indicated by their low ionization energies. Within a compound, metal atoms have relatively low attraction for electrons, as indicated by their low electronegativities. By following the trend summary in the figure below, you can see that the most reactive metals would reside in the lower left portion of the periodic table. The most reactive metal is cesium, which is not found in nature as a free element. It reacts explosively with water and will ignite spontaneously in air. Francium is below cesium in the alkali metal group, but is so rare that most of its properties have never been observed. Q: Do metals tend to gain electrons or lose electrons in chemical reactions? Choices: - develop electrons - same number of electrons - gain electrons - lose electrons A:
lose electrons
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Answer the following question given this paragraph: Another familiar example is the mixing of vinegar and olive oil. Olive oil is a nonpolar substance, while vinegar (which is mostly water and acetic acid) is polar. The result is a heterogeneous mixture that exhibits a bilayer. Q: Combining nonpolar olive oil and polar vinegar yields what type of mixture? Choices: - homogeneous - omnigeneous - amorphous - heterogeneous A:
heterogeneous
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Answer the following question given this paragraph: Chymotrypsin is found in the small intestine and catalyzes the hydrolysis of peptide bonds following aromatic amino acids. Lactase is found in the small intestine and catalyzes the hydrolysis of lactose. Pepsin is found in the stomach and catalyzes the hydrolysis of peptide bonds, primarily those that occur after aromatic amino acids. Maltase is found in the small intestine and catalyzes the hydrolysis of maltose. Q: What enzyme is found in the small intestine catalyzes the hydrolysis of lactose? Choices: - elastases - lipase - amylase - lactase A:
lactase
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Answer the following question given this paragraph: Zinc is a silvery metal that quickly tarnishes to a blue-gray appearance. This change in color is due to an adherent coating of a basic carbonate, Zn2(OH)2CO3, which passivates the metal to inhibit further corrosion. Dry cell and alkaline batteries contain a zinc anode. Brass (Cu and Zn) and some bronze (Cu, Sn, and sometimes Zn) are important zinc alloys. About half of zinc production serves to protect iron and other metals from corrosion. This protection may take the form of a sacrificial anode (also known as a galvanic anode, which is a means of providing cathodic protection for various metals) or as a thin coating on the protected metal. Galvanized steel is steel with a protective coating of zinc. Q: A protective coating of zinc to prevent corrosion is applied to steel and other metals labeled what? Choices: - polarized - battered - corroded - galvanized A:
galvanized
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