1.
Choose the term that best completes the statement:
The term ____________ is applied to any substance that cannot be made simpler without changing its chemical make-up.
Correct Answer
A. Element
Explanation
An element is the term that best completes the statement. An element is a substance that cannot be broken down into simpler substances by chemical means. It consists of only one type of atom and cannot be further simplified without changing its chemical composition.
2.
What forms when one substance dissolves another?
Correct Answer
A. Solution
Explanation
When one substance dissolves another, it forms a solution. A solution is a homogeneous mixture where the solute (the substance being dissolved) is evenly distributed and dispersed in the solvent (the substance doing the dissolving). Therefore, the correct answer is "Solution."
3.
A substance that dissolves another substance is called a ____________?
Correct Answer
A. Solvent
Explanation
A substance that dissolves another substance is called a solvent. Solvents are capable of dissolving other substances, known as solutes, to form a solution. In a solution, the solute is evenly distributed and dispersed throughout the solvent. Solvents play a crucial role in various processes, such as cleaning, chemical reactions, and pharmaceutical formulations. They have the ability to dissolve a wide range of substances, including solids, liquids, and gases.
4.
Identify the property of water that allows a water strider insect to walk on the water.
Correct Answer
A. Surface Tension
Explanation
Surface tension is the property of water that allows a water strider insect to walk on the water. Surface tension is the cohesive force between water molecules at the surface, which creates a "skin" or "film" on the water's surface. This cohesive force is strong enough to support the weight of small objects, such as the water strider's legs, allowing it to walk on the surface without sinking.
5.
Water is a universal solvent because:
Correct Answer
A. Water is polar and can dissolve more substances than any other liquid
Explanation
Water is a universal solvent because it is polar. The oxygen atom in water has a slight negative charge, while the hydrogen atoms have a slight positive charge. This polarity allows water molecules to attract and surround solute particles, breaking them apart and dissolving them. This property of water enables it to dissolve a wide variety of substances, making it a universal solvent.
6.
What is adhesion?
Correct Answer
A. Waters ability to stick to other materials
Explanation
Adhesion refers to water's ability to stick to other materials. This property allows water molecules to adhere to the surfaces of different substances, such as glass or plant tissues. It is due to the attractive forces between the water molecules and the molecules of the material it is in contact with. Adhesion plays a key role in various natural phenomena, including capillary action, where water can climb up narrow tubes against gravity, and the formation of droplets on surfaces.
7.
What is an atom?
Correct Answer
A. The smallest part of an element that is a basic unit of matter
Explanation
An atom is the smallest part of an element that is considered the basic unit of matter. It is composed of a nucleus, which contains protons and neutrons, and is surrounded by electrons. Atoms combine to form molecules and are the building blocks of all matter in the universe.