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Which sample of matter represents a mixture?*
Which sample of matter is classified as a substance?*
In which 1.0-gram sample are the particles arranged in a crystal structure?*
One mole of liquid water and one mole of solid water have different*
Which sample of matter has a crystal structure?*
At 1 atm, equal masses of H2O(s), H2O(ℓ), and H2O(g) have*
Some physical properties of two samples of iodine-127 at two different temperatures are shown in the table below.
These two samples are two different*
A sample of CO2(s) and a sample of CO2(g) differ in their*
Which sample of matter sublimes at room temperature and standard pressure?*
Which sample of CO2 has a definite shape and a definite volume?*
Base your answers to questions 11 on the information below.
Nitrogen gas and oxygen gas make up about 99% of Earth’s atmosphere. Other atmospheric gases include argon, carbon dioxide, methane, ozone, hydrogen, etc.
The amount of carbon dioxide in the atmosphere can vary. Data for the concentration of CO2(g) from 1960 to 2000 are shown in the table below.
Explain why the atmosphere is classified as a mixture.*
Base your answers to questions 12 on the information below and on your knowledge of chemistry.
A metal worker uses a cutting torch that operates by reacting acetylene gas, C2H2(g), with oxygen gas, O2(g), as shown in the unbalanced equation below.
C2H2(g) + O2(g) → CO2(g) + H2O(g) + heat
In your answer booklet, use the key to draw a particle model diagram to represent the phase of the O2(g). Your response must include at least six molecules.*
Base your answers to questions 13 on the information below and on your knowledge of chemistry.
Starting as a solid, a sample of a molecular substance is heated, until the entire sample of the substance is a gas. The graph below represents the relationship between the temperature of the sample and the elapsed time.
Using the key below, draw a particle diagram to represent the sample during interval AB. Your response must include at least six molecules.
Base your answers to questions 14 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.
Identify the phase of Ea at 310. K.*
Base your answers to questions 15 on the information below and on your knowledge of chemistry.
The table below contains selected information about chlorine and two compounds containing chlorine. One piece of information is missing for each of the substances in the table.
Identify the phase of the chlorine at STP.*