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In the formula XF2, the element represented by X can be classified as a*
Element X reacts with copper to form the compounds CuX and CuX2. In which group on the Periodic Table is element X found?*
Which statement describes a chemical property of silicon?*
Element X reacts with chlorine to form an ionic compound that has the formula XCl2. To which group on the Periodic Table could element X belong?*
In the formula for the compound XCl4, the X could represent*
In the formula XSO4, the symbol X could represent the element*
Base your answers to questions 7 on the information below.
Iron has been used for thousands of years. In the air, iron corrodes. One reaction for the corrosion of iron is represented by the balanced equation below.
Equation 1: 4Fe(s) + 3O2(g) → 2Fe2O3(s)
In the presence of water, iron corrodes more quickly. This corrosion is represented by the unbalanced equation below.
Equation 2: Fe(s) + O2(g) + H2O(ℓ) → Fe(OH)2(s)
Using equation 1, describe one chemical property of iron.*
Base your answers to questions 8 on the information below and on your knowledge of chemistry.
The diagram below represents three elements in Group 13 and three elements in Period 3 and their relative positions on the Periodic Table.
Some elements in the solid phase exist in different forms that vary in their physical properties. For example, at room temperature, red phosphorus has a density of 2.16 g/cm3 and white phosphorus has a density of 1.823 g/cm3.
Identify the element from the diagram that will react with chlorine to form a compound with the general formula XCl4.*
Base your answers to questions 9 on the information below and on your knowledge of chemistry.
Rubidium and iodine have different chemical and physical properties. Some of these properties are shown in the table below.
State the chemical property of iodine listed in this table.*
Base your answers to questions 10 on the information below and on your knowledge of chemistry.
Three elements, represented by D, E, and Q, are located in Period 3. Some properties of these elements are listed in the table below. A student’s experimental result indicates that the density of element Q is 2.10 g/cm3, at room temperature and standard pressure.
Identify the group on the Periodic Table to which element D belongs.*
Base your answers to questions 11 on the information below and on your knowledge of chemistry.
Some properties of the element sodium are listed below.
Identify one chemical property of sodium from this list.*
Base your answers to questions 12 on the information below and on your knowledge of chemistry.
In the late 1800s, Dmitri Mendeleev developed a periodic table of the elements known at that time. Based on the pattern in his periodic table, he was able to predict properties of some elements that had not yet been discovered. Information about two of these elements is shown in the table below.
Write a chemical formula for the compound formed between Ea and Cl.*
Base your answers to questions 13 on the information below.
During a fireworks display, salts are heated to very high temperatures. Ions in the salts absorb energy and become excited. Spectacular colors are produced as energy is emitted from the ions in the form of light.
The color of the emitted light is characteristic of the metal ion in each salt. For example, the lithium ion in lithium carbonate, Li2CO3, produces a deep-red color. The strontium ion in strontium carbonate, SrCO3, produces a bright-red color. Similarly, calcium chloride is used for orange light, sodium chloride for yellow light, and barium chloride for green light.
Identify the two types of chemical bonds found in the salt used to produce a deep-red color.*
Explain, in terms of element classification, why K2O is an ionic compound.*
Base your answers to questions 15 on the information below and on your knowledge of chemistry.
The Lewis electron-dot diagrams for three substances are shown below.
Describe, in terms of valence electrons, how the chemical bonds form in the substance represented in diagram 1.*
