1.
Anything that has mass and takes up space is called
Correct Answer
C. Matter
Explanation
Matter refers to anything that has mass and occupies space. It includes both solid, liquid, and gaseous substances. Bouyancy is the upward force exerted by a fluid on an object submerged in it. Mass is the measure of the amount of matter in an object. Volume is the amount of space occupied by an object. Therefore, the correct answer is Matter, as it encompasses both mass and space.
2.
When a liquid changes into a solid it is called:
Correct Answer
D. Freezing/Solidification
Explanation
When a liquid changes into a solid, it is called freezing or solidification. This process occurs when the temperature of the liquid is lowered, causing the particles to slow down and come together to form a rigid structure. During freezing, the molecules lose energy and arrange themselves in a fixed pattern, resulting in the formation of a solid. This is a common phase transition observed in substances such as water, where liquid water freezes to form ice.
3.
Which of the following is not a state of matter?
Correct Answer
B. Atom
Explanation
The question asks for a state of matter, and atom is not a state of matter. An atom is the basic unit of matter and can exist in various states of matter such as solid, liquid, or gas, but it itself is not a state of matter.
4.
The state of matter where molecules have larger space between them, are able to flow, and take the shape of the container that it is in.
Correct Answer
B. Liquid
Explanation
A liquid is a state of matter where the molecules have larger space between them compared to a solid, allowing them to flow and take the shape of the container they are in. Unlike a solid, the molecules in a liquid are not tightly packed together, which gives them the ability to move around more freely. This allows liquids to flow and take the shape of their container, making them different from solids and gases.
5.
The state of matter where molecules are packed tightly together so there is very little movement and almost no space between the molecules.
Correct Answer
A. Solid
Explanation
Solid is the correct answer because in this state of matter, the molecules are tightly packed together, resulting in very little movement and almost no space between them. Unlike in liquids or gases, the molecules in a solid are not free to move around, but instead vibrate in place. This lack of movement and close proximity of molecules gives solids their characteristic rigidity and shape.
6.
Solubility describes whether an item is able to dissolve in a particular liquid.
Correct Answer
A. True
Explanation
Solubility refers to the ability of a substance to dissolve in a specific liquid. When a substance is soluble, it means that it can mix uniformly with the liquid to form a homogeneous solution. On the other hand, if a substance is insoluble, it does not dissolve in the liquid and remains as a separate phase. Therefore, the statement "Solubility describes whether an item is able to dissolve in a particular liquid" is true, as it accurately describes the concept of solubility.
7.
Solids keep the same shape and volume.
Correct Answer
A. True
Explanation
Solids have a definite shape and volume because their particles are closely packed together and have strong intermolecular forces. This arrangement allows the particles to maintain their positions and resist changes in shape or volume. Therefore, the statement that solids keep the same shape and volume is true.
8.
When heated, solids usually change form and become gases.
Correct Answer
B. False
Explanation
Solids do not usually change form and become gases when heated. Instead, they undergo a phase change called melting, where they transform into a liquid state. The transition from a solid to a gas is called sublimation, which occurs only under specific conditions for certain substances. Therefore, the statement is false.
9.
Liquids always keep the same volume and shape.
Correct Answer
B. False
Explanation
Liquids do not always keep the same shape, but they do always keep the same volume. Unlike solids, liquids can change their shape to fit the container they are in. This is why liquids can be poured and take the shape of their container. However, the volume of a liquid remains constant, meaning it does not change regardless of the shape it takes. Therefore, the statement that liquids always keep the same volume and shape is false.
10.
In a physical change, a new substance is formed.
Correct Answer
B. False
Explanation
In a physical change, a new substance is not formed. Physical changes involve a change in the appearance or state of a substance, but the chemical composition remains the same. This means that the original substance can be reversed back to its original form without any chemical reactions occurring. Examples of physical changes include melting ice, boiling water, and tearing a piece of paper.
11.
Colour, size, shape, texture, and mass are all characteristics of objects.
Correct Answer
A. True
Explanation
The statement is true because color, size, shape, texture, and mass are indeed characteristics that can be used to describe objects. These characteristics help us differentiate and identify different objects based on their unique properties.
12.
The measure of whether an object can sink or float is called:
Correct Answer
A. Bouyancy
Explanation
Buoyancy is the measure of whether an object can sink or float in a fluid. It is determined by the density of the object compared to the density of the fluid it is placed in. If the object is less dense than the fluid, it will float, and if it is more dense, it will sink. Therefore, buoyancy is the correct answer as it directly relates to the measure of whether an object can sink or float. Solubility, viscosity, and mass do not directly determine whether an object can sink or float.
13.
Combining vinegar and baking soda is an example of a:
Correct Answer
A. Chemical change
Explanation
Combining vinegar and baking soda results in a chemical change. When vinegar (acetic acid) reacts with baking soda (sodium bicarbonate), it produces carbon dioxide gas, water, and a salt called sodium acetate. This reaction involves the breaking and forming of chemical bonds, resulting in the formation of new substances with different properties. This is characteristic of a chemical change, where the composition and properties of the substances involved are altered.
14.
Ripping a piece of paper in half is an example of a:
Correct Answer
A. pHysical change
Explanation
Ripping a piece of paper in half is an example of a physical change because it does not involve any chemical reactions. The paper remains the same substance, but its physical appearance and shape have changed. No new substances are formed during the ripping process.
15.
Ice melting into water is an example of a:
Correct Answer
A. pHysical change
Explanation
When ice melts into water, it undergoes a physical change. This is because the composition and chemical properties of the substance remain the same, only the physical state changes from solid to liquid. The molecules in the ice rearrange themselves and gain enough energy to break the intermolecular forces holding them together, resulting in the formation of water molecules. However, no new substances are formed, and the chemical composition remains unchanged. Therefore, the process of ice melting into water is a physical change.
16.
Which of the following is a reversible change?
Correct Answer
B. Folding paper
Explanation
Folding paper is a reversible change because it can be easily unfolded and returned to its original state. Unlike ripping paper or burning a popsicle stick, which cause irreversible damage, folding paper is a physical change that does not alter the composition or structure of the paper. Eating an apple is also not a reversible change as it involves a chemical change in the digestion process.
17.
Check the meaning of the safety symbol.
Correct Answer
D. Corrosive
Explanation
The correct answer is corrosive because a corrosive substance is one that can cause damage or destruction to materials or living tissues through chemical reactions. This symbol is used to indicate that a substance has the potential to cause corrosion and should be handled with caution.
18.
Check the meaning of the safety symbol.
Correct Answer
A. Explosive
Explanation
The correct answer is "Explosive" because this safety symbol is used to indicate materials or substances that have the potential to explode or cause an explosion. These materials are highly volatile and can be extremely dangerous if mishandled or exposed to certain conditions. It is important to be aware of this symbol and take appropriate precautions when working with or around explosive substances to ensure safety.
19.
Check the meaning of the safety symbol.
Correct Answer
B. Flammable
Explanation
The correct answer is "Flammable" because it refers to substances that can easily catch fire or ignite when exposed to heat, sparks, or flames. These substances have a low flash point and can pose a significant fire hazard if not handled properly.
20.
Check the meaning of the safety symbol.
Correct Answer
C. Poisonous
Explanation
The correct answer is "Poisonous" because the question asks to check the meaning of the safety symbol, and out of the given options, "Poisonous" is a safety symbol that warns about substances that are toxic or can cause harm if ingested, inhaled, or touched. This symbol is commonly used to indicate the presence of poisonous chemicals or materials that can be harmful to human health.