1.
When used the Celsius scale,what is the boiling point for water?
Correct Answer
B. 100 degrees
Explanation
The boiling point for water on the Celsius scale is 100 degrees. This means that at this temperature, water changes from a liquid to a gas state. It is an important reference point for temperature measurement and is widely used in scientific experiments and everyday life.
2.
The particle model of matter clearly states:
Correct Answer
B. All substances are made of tiny particles too small to be seen. They are always moving and have spaces in them.
Explanation
The correct answer is that all substances are made of tiny particles too small to be seen. This is a fundamental concept in the particle model of matter, which states that all matter is composed of particles that are too small to be seen with the naked eye. These particles are constantly in motion and have spaces between them. This concept helps explain various properties of matter, such as its ability to change shape and size, and its behavior under different conditions.
3.
In general, when something cools, it __________.
Correct Answer
A. Shrinks/Contracts
Explanation
When something cools, the molecules within it slow down, causing them to come closer together. This decrease in molecular motion leads to a decrease in volume, resulting in the object shrinking or contracting.
4.
The four universal states of matter are Solid, Liquid, Gas, and_______.
Correct Answer
C. Plasma
Explanation
Plasma is one of the four fundamental states of matter, alongside solids, liquids, and gasses. Unlike the other states, plasma is characterized by the absence of a fixed shape and volume because its constituent particles, such as electrons and ions, are highly energized and exist in a state of chaos. Plasmas are found in a variety of natural and artificial settings, including stars like our Sun, lightning bolts, fluorescent and neon lights, and certain types of flames.
5.
Gas turning into a solid is called:
Correct Answer
A. Deposition
Explanation
Deposition is a phase transition in which a gas transforms directly into a solid without passing through the liquid phase. This process occurs when the temperature of a gas drops below its deposition point, causing the gas molecules to lose energy and come together to form a solid. In contrast, freezing refers to the transition of a liquid to a solid, while evaporation and condensation involve the phase changes between liquid and gas. Deposition is the specific term used for the direct transition from gas to solid.
6.
Radiation can come from:
Correct Answer
E. The Sun
Explanation
The Sun is a natural source of radiation. It emits various forms of electromagnetic radiation, including visible light, ultraviolet rays, and infrared radiation. This radiation is essential for life on Earth as it provides heat and light energy. However, excessive exposure to certain types of solar radiation, such as ultraviolet rays, can be harmful to living organisms. Therefore, it is important to protect oneself from overexposure to the Sun's radiation by using sunscreen, wearing protective clothing, and seeking shade when necessary.
7.
Chemical energy is:
Correct Answer
A. Energy from Coal and wood.
Explanation
Chemical energy refers to the energy stored in the bonds of chemical compounds, such as coal and wood. When these substances undergo combustion, the bonds are broken and energy is released in the form of heat and light. Coal and wood are examples of fossil fuels, which contain stored chemical energy that can be harnessed and converted into other forms of energy, such as electricity. Therefore, the given answer "Energy from Coal and wood" correctly identifies chemical energy as the energy derived from these sources.
8.
Fossil Fuels are:
Correct Answer
A. Non-Renewable
Explanation
Fossil fuels are non-renewable resources because they are formed from the remains of plants and animals that lived millions of years ago, and their formation takes a very long time. Once these fossil fuels, such as coal, oil, and natural gas, are extracted and burned, they cannot be replaced within a human lifespan. Therefore, their supply is limited and they will eventually run out if consumed at the current rate. This is why it is important to explore and develop alternative, renewable sources of energy to reduce our dependence on fossil fuels.
9.
The fastest process of heat transfer is _____________.
Correct Answer
A. Radiation
Explanation
Radiation is the fastest process of heat transfer because it does not require any medium to transfer heat. It can occur through empty space and is not dependent on direct contact between objects. Radiation involves the emission of electromagnetic waves, such as infrared radiation, which can travel at the speed of light. Conduction and convection, on the other hand, require a medium, such as a solid or a fluid, to transfer heat and are generally slower processes.
10.
State true or false- A block of ice can radiate and absorb heat.
Correct Answer
A. True
Explanation
A block of ice can radiate and absorb heat because all objects with a temperature above absolute zero emit thermal radiation. This means that even though the ice is cold, it still emits some amount of thermal energy in the form of electromagnetic waves. Additionally, the ice can absorb heat from its surroundings through conduction or convection, allowing it to melt and increase in temperature. Therefore, it is true that a block of ice can both radiate and absorb heat.