Matter Unit Test Review

A solid is a state of matter that has a definite shape and volume. It is characterized by particles that are closely packed together and have strong intermolecular forces. Unlike squishy or slimey substances, solids maintain their shape and do not flow or take the shape of their container. Therefore, solid is the correct answer as it fits the definition of a state of matter.

Crackers are not an example of a liquid because they are solid food items. Liquids are substances that flow and can be poured, whereas crackers are dry and rigid in nature. Water and milk, on the other hand, are both examples of liquids as they have a fluid consistency.

Dew is not an example of a solid because it is a liquid. Solids have a definite shape and volume, whereas liquids take the shape of their container but have a definite volume. A doorknob and a dog house are both examples of solids because they have a definite shape and volume.

Water is composed of two elements, hydrogen and oxygen. The chemical formula for water is H2O, which means that each water molecule contains two hydrogen atoms bonded to one oxygen atom. This combination of elements gives water its unique properties, such as its ability to dissolve many substances, its high boiling and melting points, and its role as a universal solvent.

When you change an object's basic characteristics like size and shape, it is considered a physical change. This is because physical changes do not alter the chemical composition or identity of the substance. In this case, altering the size and shape of an object does not change its chemical properties or create a new substance.

An atom is the smallest complete piece of an element. It is composed of protons, neutrons, and electrons. Protons and neutrons are located in the nucleus of the atom, while electrons orbit around the nucleus. Atoms are the building blocks of matter and cannot be broken down further without losing their chemical properties.

The correct answer is "packed closely together" because in a solid state, the molecules are tightly packed and held together by strong intermolecular forces. This arrangement gives solids their fixed shape and volume. The molecules in solids have minimal movement and vibrate in fixed positions, which is why they are closely packed together.

This answer is correct because "takes up space" is a fundamental characteristic of matter. Matter exists in the form of solid, liquid, or gas, and regardless of its state, it occupies physical space. This can be observed through simple everyday experiences, such as placing objects in a container or feeling the resistance when trying to move through a crowded room. The other options, "can be measured on a balance" and "has a specific shape," are not universally applicable to all types of matter, making them incorrect.

The process of changing from liquid water to a solid is called freezing.

The periodic table is used to organize the known elements. It arranges the elements in order of increasing atomic number and groups them based on their chemical properties. The table provides valuable information about each element, such as its symbol, atomic mass, and electron configuration. It allows scientists to easily identify and study the properties and relationships between different elements, making it an essential tool in the field of chemistry.

A shadow is not an example of matter because it is simply the absence of light caused by an object blocking the light source. Matter, on the other hand, refers to anything that has mass and occupies space. Both soup and stairs are examples of matter as they have mass and occupy space.

The correct answer is spread far apart. In a gas, the molecules have high kinetic energy and move rapidly in all directions. Due to this constant motion, the molecules are able to spread out and occupy a large volume. Therefore, the molecules in a gas are spread far apart from each other.

Heat is a form of energy. It is the transfer of thermal energy from one object to another due to a difference in temperature. Heat can be produced by various sources such as burning fuel, electricity, or even the sun. It is measured in units of joules or calories. Therefore, "energy" is the correct answer as it accurately describes heat as a type of energy.

The piece of an atom that has a positive charge is called a proton. Protons are subatomic particles found in the nucleus of an atom. They have a positive electrical charge and are approximately 1,836 times heavier than electrons. The number of protons in an atom determines its atomic number and defines the element it belongs to.

Solids are the state of matter that maintain their own shape. Unlike liquids and gases, which can flow and change shape, solids have a fixed shape and volume. The particles in a solid are tightly packed together and have strong intermolecular forces holding them in place. This allows solids to maintain their shape even when subjected to external forces.

Molecules are constantly in motion due to their kinetic energy. This movement can be in the form of vibrations, rotations, or translations. The random motion of molecules allows them to interact with other molecules and participate in chemical reactions. Therefore, the correct answer is "moving".

Burning is an example of a chemical change because it involves a chemical reaction. During burning, a substance reacts with oxygen to produce new substances with different properties. This process is irreversible and usually accompanied by the release of heat and light. Therefore, burning is not a physical change, which refers to a change in the state or appearance of a substance without altering its chemical composition. "Special" is not a valid option as it does not accurately describe the type of change involved in burning.

The molecules in a liquid are spread apart. In a liquid, the molecules have more freedom of movement compared to a solid, allowing them to move and flow past each other. While they are still close enough to interact with each other, they are not as tightly packed as in a solid. This spacing between molecules is what gives liquids their ability to flow and take the shape of their container.

An atom's protons will always be found in the nucleus. The nucleus is the central part of an atom that contains the protons and neutrons. Protons are positively charged particles, and they are located in the nucleus along with the neutrons. The electrons, which are negatively charged particles, are found in the electron shells surrounding the nucleus. Therefore, the correct answer is nucleus.

Melting is the correct answer because it refers to the process of changing a solid into a liquid by increasing its temperature. This occurs when the solid absorbs enough heat energy to break the bonds between its particles and transition into a liquid state. Boiling, on the other hand, is the process of changing a liquid into a gas, while freezing is the process of changing a liquid into a solid.

Energy is not a common property of matter because it is not an inherent characteristic of all forms of matter. While mass and volume are physical properties that can be measured and observed in any form of matter, energy is a separate entity that can be transferred or transformed but is not considered an inherent property of matter itself.

The protons and neutrons in an atom are contained in the nucleus. The nucleus is the central part of an atom, consisting of protons and neutrons. It has a positive charge due to the presence of protons and is surrounded by electron shells, where the electrons are located. The nucleus is responsible for the majority of an atom's mass and determines the element to which the atom belongs.

The elements on the periodic table are organized by their atomic number. The atomic number of an element represents the number of protons in the nucleus of its atoms. This number determines the element's identity and its position on the periodic table. The arrangement of elements by atomic number allows for a systematic organization that reflects the periodic trends in their properties. Atomic mass is not used for organizing the elements on the periodic table, although it is listed for each element. Atomic symbol refers to the abbreviation used to represent an element, but it is not the basis for organizing the elements on the table.

The piece of an atom that has a negative charge is called an electron. Electrons are subatomic particles that orbit the nucleus of an atom and carry a negative charge. They play a crucial role in chemical reactions and the behavior of atoms in various substances.

A liquid is the state of matter that takes the shape of the container it is put into. Unlike solids, which have a fixed shape, liquids are able to flow and adapt to the shape of their container. This property is due to the particles in a liquid being loosely packed and able to move around more freely compared to solids. Gases also take the shape of their container, but they have a much higher degree of freedom of movement and are not as tightly packed as liquids.

When an object is changed into a completely new object, it implies that a chemical reaction has occurred. Chemical changes involve the rearrangement of atoms and molecules to form new substances with different properties. This is in contrast to physical changes, which do not result in the formation of new substances. Therefore, the correct answer is chemical.

The amount of matter has not changed since the Earth was formed because matter cannot be created or destroyed, only transformed or rearranged. The Earth has a finite amount of matter, which has been recycled and redistributed through various processes such as volcanic activity, erosion, and the water cycle. While the distribution and form of matter may have changed over time, the total amount remains constant.

Atoms can combine with other types of atoms to form molecules. A molecule is a group of two or more atoms that are chemically bonded together. This bonding occurs through the sharing or transfer of electrons between atoms. Molecules can be made up of atoms of the same element or different elements. This process of combining atoms to form molecules is fundamental to chemistry and plays a crucial role in the formation of various compounds and substances.

Plasma is considered as the fourth state of matter because it is a super charged and energy filled matter. It is formed when a gas is heated to very high temperatures or when electrons are stripped away from atoms. Plasma consists of charged particles, such as ions and free electrons, which makes it electrically conductive. It is commonly found in stars, lightning, and fluorescent lights.

A gas is the state of matter that fills all the available space it can. Unlike solids and liquids, gases have particles that are not closely packed together and are free to move around. This allows gases to expand and fill the entire volume of a container.

Mass is the measurement of the amount of matter that exists. It represents the quantity of matter in an object and is often measured in units such as kilograms or grams. Mass is different from weight, as weight is the force exerted on an object due to gravity. Inertia is the tendency of an object to resist changes in its motion, and volume is the amount of space occupied by an object. Therefore, the correct answer is mass.

The correct answer is conservation of mass. This principle states that the total mass of a closed system remains constant over time, regardless of any physical or chemical changes that may occur within the system. This means that while matter can undergo various transformations, such as changing states or undergoing chemical reactions, the total amount of matter present remains unchanged. This concept is a fundamental principle in physics and chemistry.

Inertia is the property of matter that resists any change in its state of motion. It is the tendency of an object to stay at rest or continue moving at a constant velocity unless acted upon by an external force. This means that without an outside force, matter will not change its motion, whether it is at rest or in motion. Therefore, matter cannot move without an outside force due to inertia.