Corrections on Learning Checkpoint 1 by Aiden G

A student creates the following particulate view of the water particles in a tank used for the classroom frogs. Shaded circles represent water particles, as shown in the legend. The species of frog lives in the Amazon rain forest, and it needs an environment with high humidity to survive. High-humidity environments have more water particles in the air than do low-humidity environments. The student increases the temperature of the tank while keeping it closed. Which of the following best represents the distribution of water particles in the tank after the increase in temperature?

Less water more gas

Which of the following explains the observation that, for the same substances, the density of a gas is much less than the density of a solid?

The average distance between particles in a gas is larger than the average distance between particles in a solid.

The figure represents a solid block of copper metal at 30°C . Which of the following best represents the particle arrangements as a student tips the beaker, which is kept at 30°C?

The block should still be in a neat arranged way at an angle

A student has drawn this model and says it shows what happens when a liquid changes to a gas. The diagram can best be used to illustrate which of the following?

The density of a gas is less than that of a liquid.

A student determines the mass and volume of several pieces of the same metal. To determine the volume, the student places the metal in the water, then calculates the volume of water displaced by the metal sample. The student plots the data, as shown on the graph. The density of the metal is closest to which of the following?

2.7 g/mL

A student creates the following particulate view of the water particles in a tank used for the classroom frogs. Shaded circles represent water particles, as shown in the legend. The species of frog lives in the Amazon rain forest, and it needs an environment with high humidity to survive. High-humidity environments have more water particles in the air than do low-humidity environments. When taking care of the frogs, the student adds more water to the tank. A view of the amount of water measured is shown. What should the student record as the amount of water added to the tank, to the appropriate precision?

43 mL

The diagrams show two forms of the same substance, form X and form Z, that differ in the arrangement of their particles. Which of the following statements about the relative densities of the two forms is correct?

Form Z is more dense because the mass of form Z is greater than the mass of the same volume of form X.

A student fills two syringes: one with air and the other with an equal volume of water. After capping the syringes, the student applies the same amount of pressure to the plungers and records observations about the change in volume. Based on the particle model of matter, which of the following statements best explains the student's observations that the volume of the gas decreases greatly but the volume of the liquid does not change noticeably?

Gases are more readily compressed than liquids are because there is more space between the particles in a gas than in a liquid.

A student determines the mass and volume of several pieces of the same metal. To determine the volume, the student places the metal in the water, then calculates the volume of water displaced by the metal sample. The student plots the data, as shown on the graph. Which of the following pieces glassware should use to determine the volume of the metal samples?

Graduated Cylinder

Students in a different class use a similar model to represent their tank, which houses desert toads that live in environments with very low humidity. Which of the following sentences can the students use to support that their model represents a low-humidity environment.

High-humidity environments have more water particles in the air than do low-humidity environments.

Chromium metal has a density of 7.2 g/cm3. Mass and volume data for five metals are given in the table. Which TWO of the metals have a density greeter than that of chromium?

Copper & Iron

Each of the three containers contains a solid, a liquid, or a gaseous substance. One particle of each substance is represented in these diagrams. The arrows show the relative movement of the particles. Based on the movement of the particles, drag the word that best describes the substance represented in each diagram to the appropriate box.

Diagram 1: Liquid Diagram 2: Gas Diagram 3: Solid

The particle diagram represents a sample of helium in a sealed container at constant volume. The length of each arrow represents the relative speed of each particle. Which particle diagram represents the same sample after heating, and what is the correct justification for that choice?

Diagram Y represents the gas sample at a higher temperature because the particles have a higher average speed when heated.