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Is it true that a temperature change in substances always indicates that the state of the substance has chang?
Of course not ! You may fill a teapot with very cold water and leave it on the stove
until the water is very hot, without changing the water from its liquid state.
I have also observed from time to time that when my black dogs lie in the direct sun,
their fur becomes noticeably warmer without changing its state.
What else can I help you with?
Is heat always transferred from a warmer substance to a cooler substance?
Yes. (That's why refrigerators are a kind of a trick - an inefficient one.)
Flow of thermal energy from warmer to cooler substances?
Thermal energy flows from warmer substances to cooler substances through the process of heat transfer. This transfer occurs until both substances reach thermal equilibrium, where they have the same temperature. This flow of thermal energy follows the second law of thermodynamics, which states that heat always flows from higher temperature regions to lower temperature regions.
Equal volumes always mean equal masses?
Not necessarily. Equal volumes do not always mean equal masses because different substances have different densities. Denser substances will have more mass in a given volume compared to less dense substances.
Is the kelvin temperature of a substance directly proportional to the total kinetic energy of the particles in the substance?
Yes, the Kelvin temperature of a substance is directly proportional to the average kinetic energy of the particles in the substance. The higher the temperature in Kelvins, the higher the average kinetic energy of the particles.
Do all substances warm up at the same rate?
no because energy always flows from the hotter object to the cooler object. it will continue to flow until the two objects reach the same temperature. when both molecules are at the same temperature, the molecules will have the same kinetic energy.
The density of a substance is the same for all samples of the substances?
Density is simply the mass divided by volume. This means that it is the amount of the substance in a specific unit of space. Because a pure substance indicates that it is exactly that, a substance made of a specific combination of elements, it will always have the same density because those elements can only take one form in order for it to be pure.
When comparing the freezing point and the boiling point of different substances the?
The freezing point is the temperature at which a substance transitions from a liquid to a solid state, while the boiling point is the temperature at which a substance transitions from a liquid to a gas state. These points are characteristic properties of each substance and can vary depending on the type of substance.
A solution a substance or a mixture?
It is always a mixture of two substances: the solute and the solvent.
Why should you always quote the temperature when giving the solubility of a substance?
because u can
Is dirt a heterogeneous or homogeneous substance?
Heterogeneous because it contains many different substances and is not always the same in composition.
Is heat always transferred from a warmer substance to a cooler substance?
Yes. (That's why refrigerators are a kind of a trick - an inefficient one.)
Is the difference between a pure substance and a mixture always easy to observe?
No, the difference between a pure substance and a mixture is not always easy to observe. While pure substances have definite chemical compositions and properties, mixtures consist of two or more substances physically combined. Some mixtures can be challenging to distinguish from pure substances based on visual observations alone.
Is a sharp melting point for a crystalline organic substance always indicates a pure single compound?
In general, a sharp melting point for a crystalline organic substance can suggest a pure single compound. However, impurities or different polymorphs can also affect the sharpness of the melting point. Additional analysis, such as TLC or NMR, may be needed to confirm the purity of the compound.
Describe what a pure material or substance is?
These are substances that contain only one type of atoms/molecules. For example, diamond is a pure substance. Diamonds are made of strictly carbon atoms. Melting points and Boiling points of pure substances always remain constant !
How does density of a substance change with temperature and name a substance that does not strictly follow this rule.?
In general, as the temperature of a substance increases, it's density decreases. One exception of this is water. as liquid water approaches it's freezing point, the water molecules rearrange themselves into a lattice structure, actually making it less dense. This is why ice floats on top of water.
What are the properties of matters?
PROPERTIES OF MATTER 1. A Substance may be identified by certain Qualities, or Traits. A QUALITY OR TRAIT THAT IDENTIFIES A SUBSTANCE IS CALLED A PROPERTY. 2. The property of a substance stays the SAME even if the Volume changes. 3. COLOR, MASS, SMALL, DENSITY, AND COMPOSITION ARE ALL EXAMPLES OF PROPERTIES THAT CAN HELP SCIENTIST IDENTIFY SUBSTANCES. 4. A PROPERTY THAT ALWAYS STAYS THE SAME IS CALLED A CHARACTERISTIC PROPERTY BECAUSE IT IS A CHARACTERISTIC OF A PARTICULAR KIND OF MATTER. 5. EVERY SUBSTANCE HAS TWO KINDS OF PROPERTIES - PHYSICAL PROPERTIES AND CHEMICAL PROPERTIES. 6. A PHSICAL PROPERTY is a property of matter that can be OBSERVED or MEASURED WITHOUT CHANGING the composition of the substance. 7. Physical properties are often used to identify substances. 8. SOME PHYSICAL PROPERTIES OF MATTER: A. BIOLING POINT - The temperature at which a substance changes from a liquid to a gas. B. CONDENSATION POINT - The temperature at which a substance changes from a gas to liquid; same temperature as boiling point. C. DENSITY - The mass of a specific volume of substance. D. FREEZING POINT - The temperature at which a substance changes from a liquid to a solid; same temperature as melting point. E. MELTING POINT - The temperature at which a substance changes from a solid to a liquid. F. RESISTANCE - The opposition of a substance has to the flow of electric current. G. SOLUBILITY - The degree to which a substance will dissolve in a given amount of another substance, such as water.
What kind of changes in substances are always physical changes?
The kinds of changes in substances that are always physical changes are changes in the state. This is the change from solid, to liquid and then to gas and the reverse.
