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Which sample of CO2 has a definite shape and a definite volume?*
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*
At 1 atm, equal masses of H2O(s), H2O(ℓ), and H2O(g) have*
A sample of CO2(s) and a sample of CO2(g) differ in their*
In which 1.0-gram sample are the particles arranged in a crystal structure?*
Which sample of matter has a crystal structure?*
One mole of liquid water and one mole of solid water have different*
A gas changes directly to a solid during*
Which sample of matter sublimes at room temperature and standard pressure?*
Which equation represents sublimation?*
Base your answers to questions 11 on the information below.
Starting as a gas at 206°C, a sample of a substance is allowed to cool for 16 minutes. This process is represented by the cooling curve below.
Using the key below, draw two particle diagrams to represent the two phases of the sample at minute 4. Your response must include at least six particles for each diagram.
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Base your answers to questions 12 on the information below and on your knowledge of chemistry.
Paintball is a popular recreational activity that uses a metal tank of compressed carbon dioxide or nitrogen to launch small capsules of paint. A typical tank has a volume of 508 cubic centimeters. A 340.-gram sample of carbon dioxide is added to the tank before it is used for paintball. At 20.°C, this tank contains both CO2(g) and CO2(ℓ). After a paintball game, the tank contains only CO2(g).
In the box below, use the key to draw a particle diagram to represent the two phases of CO2 in a newly filled tank. Your response must include at least six molecules of CO2 in each phase.
Base your answers to questions 13 on the information below and on your knowledge of chemistry.
At standard pressure, water has unusual properties that are due to both its molecular structure and intermolecular forces. For example, although most liquids contract when they freeze, water expands, making ice less dense than liquid water. Water has a much higher boiling point than most other molecular compounds having a similar gram-formula mass.
Explain why H2O(s) floats on H2O(ℓ) when both are at 0ºC.*
Base your answers to questions 14 on the information below and on your knowledge of chemistry.
A technician recorded data for two properties of Period 3 elements. The data are shown in the table below.
State the phase of chlorine at 281 K and 101.3 kPa.*
Base your answers to questions 15 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.*