1.
The kinetic theory is an explanation of how particles in matter behave.
Correct Answer
A. True
Explanation
The given statement is true because the kinetic theory is indeed an explanation of how particles in matter behave. According to this theory, all matter is made up of tiny particles that are constantly in motion. These particles have kinetic energy, which determines their speed and temperature. The kinetic theory helps explain various properties of matter, such as the expansion and contraction of solids, liquids, and gases with changes in temperature. It also provides insights into the behavior of gases, such as the relationship between pressure, volume, and temperature in ideal gases.
2.
Not all matter is composed of small particles
Correct Answer
B. False
Explanation
The statement "Not all matter is composed of small particles" is false. According to the atomic theory, all matter is made up of small particles called atoms. Atoms are the basic building blocks of matter and cannot be further divided into smaller particles. Therefore, all matter is composed of small particles.
3.
The particles are ______________ with each other and the walls of their container.
Correct Answer
B. Colliding
Explanation
The particles in a container are constantly in motion and interact with each other and the walls of the container through collisions. These collisions result in the transfer of energy and momentum between the particles and the container, causing them to bounce off each other and the walls. Therefore, the correct answer is "colliding".
4.
Atoms in ________________ are held tightly in place by the attraction between the particles.
Correct Answer
C. Solids
Explanation
Solids are made up of particles that are tightly packed together, which results in strong intermolecular forces of attraction between the particles. This strong attraction holds the atoms in solids tightly in place, preventing them from moving freely. In contrast, gases and liquids have weaker intermolecular forces, allowing the particles to move more freely.
5.
_______________means the average kinetic energy of particles in the substance, or how fast the particles are moving.
Correct Answer
A. Temperature
Explanation
Temperature refers to the average kinetic energy of particles in a substance, or how fast the particles are moving. It is a measure of the hotness or coldness of an object or environment. The higher the temperature, the faster the particles are moving and the more kinetic energy they possess. Conversely, the lower the temperature, the slower the particles are moving and the less kinetic energy they have. Temperature is measured using various scales such as Celsius, Fahrenheit, and Kelvin.
6.
___________________is the pressure of the vapor in a liquid equal to the external pressure on the liquid.
Correct Answer
B. Boiling point
Explanation
The boiling point is the temperature at which the vapor pressure of a liquid is equal to the external pressure on the liquid. At this temperature, the liquid molecules have enough energy to overcome the external pressure and escape into the gas phase. Therefore, the vapor pressure inside the liquid is equal to the external pressure, resulting in the liquid boiling.
7.
Water freezes at
Correct Answer
A. 0 c
Explanation
Water freezes at 0°C. This is the temperature at which water changes from its liquid state to a solid state, forming ice. At temperatures below 0°C, water molecules slow down and begin to arrange themselves into a crystalline structure, resulting in the formation of ice. Therefore, 0°C is the freezing point of water.
8.
A state with no definite shape and definite volume
Correct Answer
A. Liquid
Explanation
A state with no definite shape and definite volume is a characteristic of a liquid. Liquids do not have a fixed shape and can take the shape of their container. They also have a definite volume, meaning they cannot be compressed. This is in contrast to solids, which have a definite shape and volume, and gases, which have no definite shape or volume. Therefore, the correct answer is liquid.
9.
Gases do not have a fixed volume or shape.
Correct Answer
A. True
Explanation
Gases do not have a fixed volume or shape because the particles in a gas are in constant motion and spread out to fill the space available to them. Unlike solids and liquids, which have a fixed volume and shape, gases can expand or contract to fit the container they are in. This is due to the weak forces of attraction between gas particles, allowing them to move freely and independently of each other. Therefore, it is true that gases do not have a fixed volume or shape.
10.
Is the amount of energy required for the liquid at its boiling point to become a gas.
Correct Answer
B. Heat of vaporization
Explanation
Heat of vaporization refers to the amount of energy required for a liquid at its boiling point to transition into a gas. This process involves breaking the intermolecular forces between the liquid molecules and converting them into a gaseous state. The heat of vaporization is a characteristic property of a substance and varies depending on the specific substance. It is an important concept in understanding phase changes and the behavior of substances at different temperatures.
11.
Is matter consisting of positively and negatively charged particles, found in the sun's core.
Correct Answer
C. Plasma
Explanation
Plasma is the correct answer because it is a state of matter that consists of positively and negatively charged particles. It is found in the sun's core, where extremely high temperatures cause atoms to lose their electrons and become ionized. This ionized gas is known as plasma and is different from solids and liquids, which do not have charged particles.
12.
Thermal expansion
Correct Answer
B. Is an increase in the size of a substance when the temperature is increased.
Explanation
Thermal expansion is the phenomenon where a substance increases in size when its temperature is increased. This occurs because as the temperature rises, the particles in the substance gain more energy and move faster, causing them to spread out and take up more space. This expansion can be observed in various materials, such as liquids, gases, and solids. When the temperature decreases, the particles lose energy and move slower, causing the substance to contract or decrease in size. Therefore, the correct answer is that thermal expansion is an increase in the size of a substance when the temperature is increased.
13.
The air in the balloon is heated, causing the distance between the particles in the air to increase.
Correct Answer
C. Thermal expansion
Explanation
When the air inside the balloon is heated, the particles in the air gain energy and move faster. This increased energy causes the particles to spread out and move further apart from each other, resulting in an increase in the volume of the air. This phenomenon is known as thermal expansion, where a substance expands when its temperature increases. Therefore, the correct answer is thermal expansion.
14.
The particles in the liquid in the narrow thermometer tube start to move farther apart as their motion increases.
Correct Answer
B. Thermal expansion
Explanation
As the particles in the liquid gain thermal energy, they start to move faster and their kinetic energy increases. This increased motion causes the particles to move farther apart, leading to an expansion of the liquid. This phenomenon is known as thermal expansion, where substances expand in response to an increase in temperature.
15.
What is the strange behavior of water?
Correct Answer
B. Expands when cooled.
Explanation
Water exhibits a unique behavior where it expands when it is cooled. This phenomenon is due to the structure of water molecules. As water cools, the molecules slow down and come closer together, causing the volume to decrease. However, when the temperature reaches around 4°C, the water molecules start to form a crystal lattice structure, causing them to arrange themselves in a way that takes up more space. This expansion upon cooling continues until the water freezes into ice. This strange behavior of water is crucial for various natural processes, such as the floating of ice on water bodies, which insulates the water beneath and supports aquatic life during winter.
16.
These solids lack the highly ordered structure found in crystals, and don't have a definite temperature to melt like volcanic glass.
Correct Answer
A. AmorpHous solids
Explanation
Amorphous solids lack the highly ordered structure found in crystals, which means their atoms or molecules are not arranged in a regular pattern. This lack of order gives them a characteristic of not having a definite temperature to melt, unlike volcanic glass. In contrast, crystalline solids have a highly ordered arrangement of atoms or molecules and a specific melting point. Plasma solids are not a recognized category of solids, so they are not the correct answer.
17.
Substances start to flow during the melting phase similar to a liquid, but they do not lose their ordered arrangement completely, as most substances do like (LCD) screens.
Correct Answer
B. Liquid crystals
Explanation
Liquid crystals are a unique state of matter that exhibit properties of both liquids and solids. During the melting phase, substances with liquid crystal properties start to flow like a liquid, but they retain some level of ordered arrangement, unlike most substances that completely lose their ordered arrangement. This is what distinguishes liquid crystals from crystalline solids and amorphous solids.
18.
Thermal energy is
Correct Answer
A. Total of kinetic and potential energy of the particles
Explanation
Thermal energy refers to the total energy possessed by the particles in a substance. This energy is a combination of both kinetic energy, which is the energy of motion of the particles, and potential energy, which is the energy associated with the position or arrangement of the particles. Therefore, the correct answer is that thermal energy is the total of kinetic and potential energy of the particles.