Video Transcriptchemical properties. What are they? So, a chemical property is when the identity of something changes from one thing to another. For example, the atom can become something else. Gones are breaking. The molecule Is binding to a different one, forming a new molecule. So the identity changes, mm hmm. Some examples of this could be combustion rusting things like that. Whereas a physical property is just when it looks different. But the but the um identity is still the same. For for example, boiling is a physical property because It's still H20. It's just going from a liquid to a gas. But it's um chemical identity, which is the fact that the molecule has one oxygen and two hydrogen ions that is still staying the same. So a chemical property, the identity changes physical property identity is the same. Show We are all surrounded by matter on a daily basis. Anything that we use, touch, eat, etc. is an example of matter. Matter can be defined or described as anything that takes up space, and it is composed of miniscule particles called atoms. It must display the two properties of mass and volume. The different types of matter can be distinguished through two components: composition and properties. The composition of matter refers to the different components of matter along with their relative proportions. The properties of matter refer to the qualities/attributes that distinguish one sample of matter from another. These properties are generally grouped into two categories: physical or chemical. Physical Properties and ChangesPhysical properties can be observed or measured without changing the composition of matter. Physical properties are used to observe and describe matter. Physical properties of materials and systems are often described as intensive and extensive properties. This classification relates to the dependency of the properties upon the size or extent of the system or object in question. An intensive property is a bulk property, meaning that it is a physical property of a system that does not depend on the system size or the amount of material in the system. Examples of intensive properties include temperature, refractive index, density, and hardness of an object. When a diamond is cut, the pieces maintain their intrinsic hardness (until their size reaches a few atoms thick). In contrast, an extensive property is additive for independent, non-interacting subsystems. The property is proportional to the amount of material in the system. Intensive properties: A physical property that will be the same regardless of the amount of matter.
Extensive Properties: A physical property that will change if the amount of matter changes.
Physical Change Change in which the matter's physical appearance is altered, but composition remains unchanged. A physical change takes place without any changes in molecular composition. The same element or compound is present before and after the change. The same molecule is present through out the changes. Physical changes are related to physical properties since some measurements require that changes be made. The three main states of matter are: Solid, Liquid, Gas
Example \(\PageIndex{1}\): Physical Change When liquid water (\(H_2O\)) freezes into a solid state (ice), it appears changed; However, this change is only physical as the the composition of the constituent molecules is the same: 11.19% hydrogen and 88.81% oxygen by mass. Figure \(\PageIndex{2}\): Physical Change: Ice Melting is a physical change. from Wikipedia. Chemical Properties and ChangesChemical properties of matter describes its "potential" to undergo some chemical change or reaction by virtue of its composition. What elements, electrons, and bonding are present to give the potential for chemical change. It is quite difficult to define a chemical property without using the word "change". Eventually you should be able to look at the formula of a compound and state some chemical property. At this time this is very difficult to do and you are not expected to be able to do it. For example hydrogen has the potential to ignite and explode given the right conditions. This is a chemical property. Metals in general have they chemical property of reacting with an acid. Zinc reacts with hydrochloric acid to produce hydrogen gas. This is a chemical property. Chemical change results in one or more substances of entirely different composition from the original substances. The elements and/or compounds at the start of the reaction are rearranged into new product compounds or elements. A CHEMICAL CHANGE alters the composition of the original matter. Different elements or compounds are present at the end of the chemical change. The atoms in compounds are rearranged to make new and different compounds. Example \(\PageIndex{1}\): Corrosion of Metals Corrosion is the unwanted oxidation of metals resulting in metal oxides. \[2 Mg + O_2 \rightarrow 2 MgO\] Figure \(\PageIndex{3}\): Chemical Change: A burning magnesium ribbon with very short exposure to obtain oxidation detail. from Capt. John Yossarian (Wikipedia)ProblemsThe following questions are multiple choice. 1. Milk turns sour. This is a ________________
2. HCl being a strong acid is a __________, Wood sawed in two is ___________
3. CuSO4 is dissolved in water
4. Aluminum Phosphate has a density of 2.566 g/cm3
5. Which of the following are examples of matter?
6. The formation of gas bubbles is a sign of what type of change? 7. True or False: Bread rising is a physical property. 8. True or False: Dicing potatoes is a physical change. 9. Is sunlight matter? 10. The mass of lead is a _____________property. Solutions
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Which best describes chemical properties?Chemical properties describe the characteristic ability of a substance to react to form new substances; they include its flammability and susceptibility to corrosion. All samples of a pure substance have the same chemical and physical properties.
What are three terms that describe chemical properties of matter?Here are some examples of chemical properties:. Reactivity with other chemicals.. Toxicity.. Coordination number.. Flammability.. Enthalpy of formation.. Heat of combustion.. Oxidation states.. Chemical stability.. Which statement best describes most chemical changes?Out of the given 4 options, the correct option is option a. During a chemical reaction both the identity and the properties of a substance change. Chemical reaction between two substances occurs to form a new substance which is completely different.
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