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Is it true that a temperature change in substances always indicates that the state of the substance has chang?
Wiki User
∙ 9y ago
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.
Wiki User
∙ 9y ago
Wiki User
∙ 9y agoNo, that is not true.
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Do molecules always move?
Yes, as long as the temperature of the substance they comprise is warmer than Absolute Zero.
What is ALWAYS true about the temperature of a substance during a phase change?
Its constant (more-or-less, since energy is used in changing state rather than increasing temperature)
A graph showing zero slope for the velocity vs time always indicates that the object is not moving?
No. It always indicates that the object is not accelerating.
Which state of matter has molecules vibrating next to each other?
All substances always vibrate and shake next to each other: it's how we perceive temperature. I don't think I quite understand this question. But this may help: If a substance is in solid form, it is the most compact. The molecules are vibrating next to each other very closely. If a substance is in liquid form, it is somewhat compact. Molecules are vibrating next to each other, but not as closely. If a substance is in a gaseous form, it is spread out and crazy: and like every other state of matter, the molecules are vibrating next to each other.
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.
Is a sharp melting point for a crystalline organic substance always indicates a pure single compound?
Nope; not always. So the answer would be false. You have to realize that there might be impure substances mixed. Likewise impure substance can either lower the melting point or increase it :)M. Bilal :)
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.
A solution a substance or a mixture?
It is always a mixture of two substances: the solute and the solvent.
Does the composition of a substance always stay the same?
The composition of pure substances, such as elements and compounds, are always the same. The composition of mixtures can vary.
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.
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.
What is the definition of pure substances?
A pure substance is a substance that consists solely of the same atoms/molecules.So a volume of water that contains only H2O is a pure substance. A block of iron that contains only Fe atoms is pure substance. A pure substance can be composed of atoms or molecules as I said before BUT they have to be exactly the same.A substance that has constant chemical composition and characteristics
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 !
What pH indicates that the most hydroxide ions are present?
The highest pH value in a group of such values indicates that the greatest concentration of hydroxide ions is present in the substance with the highest pH. This is true because a higher pH indicates a lower concentration of hydrogen ions, and the product of the molar concentrations of hydrogen and hydroxide ions must always be 10-14 at standard temperature and pressure in a mixture that is mostly water.
Do molecules always move?
Yes, as long as the temperature of the substance they comprise is warmer than Absolute Zero.
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.
