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Is always obvious when a substance undergoes a chemical changes yes or no?
Wiki User
∙ 12y ago
chemical changes form to completely different things so yes
Wiki User
∙ 12y ago
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How can you tell a chemicall reaction has happened?
The most obvious event to look for to indicate a chemical reaction is the production of heat. All chemical reactions produce heat.
how do people use energy released during chemical changes?
The 2 most common and obvious are: Electricity from batteries. (Photovoltaic cells use physical rather than chemical changes.) Heat from combustion - for heating buildings, industrial processes etc., and in heat-engines (internal-combustion, steam-turbine, gas-turbine, and jet - in former times, hot-air engines and steam engines).
What substance is the byproduct of the chemical equation?
Some chemical equations don't have byproducts. The most obvious one is hydrogen and oxygen. React them and all you get is water. In other equations, there are definitely byproducts...if you were crazy enough to react sodium hydroxide and hydrochloric acid (do this in a fume hood, please) you will get sodium chloride and water. The water would be the byproduct.
What is one other change in chemical changes?
There are many different kinds of chemical reactions, which involve many different kinds of chemical changes. All of these changes are observable, but some are more easily observable than others. Fire is an example of a chemical change that is extremely obvious and easily observed. When a piece of wood burns, it is changed into ash, as well as gases which are temporarily visible in the form of flame. We observe a dramatic change in temperature, since fire produces a lot of heat. Solid logs can be turned into gaseous carbon dioxide and water vapor, along with ashes and various other combustion products. But fire is not the only kind of chemical reaction. You can take two transparent aqueous solutions, mix them together, and have a chemical reaction take place that is invisible to the eye, but which can be analysed with various tests or equipment. One protein can be transformed into another protein, and both types of protein can look exactly the same. Chemical identity can be very subtle. Some chemical reactions involve visible changes of color, but most do not. Chemical reactions can produce lots of heat, or very little heat (but with a sensitive thermometer, you can detect even small changes in temperature). Chemical reactions can cause a change of phase (as from solid to gas) but they usually don't. Chemical reactions can alter solubility, so that an insoluble product is formed, which as a result causes a visible precipitate. There are many other possible results of a chemical reaction.
What are some ways a nail can undergo a chemical change?
The most obvious one is when it rusts. Rust is the oxidization of iron.
Is it obvious when a substance undergoes a chemical change?
Yes because, If you had a BRAND NEW bike, And it wasnt rusted or had any cracks at ALL, It would be obvious that if in a couple years it was completely rusted it would be noticable, In other words ( It is obvious that a substance undergoes a chemicaL WHICH MEANS that a chemical change has happened.) Jade
How are physical and chemical changes different in two ways?
a physical change can be reversed but a chemical changes is not. you can all tell the different from a physical and chemical change by seeing if the color or if the substances is still in it normal element and it a chemical change if it has been change to a new substances like a burn paper change to Ashes. It is all most a physical change but it can not be reversed back.
What are the changes caused by earths yearlong orbit?
The seasons are the most obvious changes.
How can you detect rat poison in marijuana?
It should be fairly obvious. It manifests itself as a chemical taste. Your pot will sometimes have a chemical smell aswell. Most obvious of giveaways is the bitter chemical taste. Legalize it!!
Distinguish Between physical and chemical properties or changes in matter?
chemical properties of matter is matter based on its ability to participate in chemical reactions and form new substances .chemical property of matter is chemical that do change the chemical nature of the matter.there are also 2 chemical properties of matter:1. Combustibility - How easily it will react/explode with another substance.2. Reaction with Acid - Pretty much self explanatory...How it will react when combined with acid.
How can you tell a chemicall reaction has happened?
The most obvious event to look for to indicate a chemical reaction is the production of heat. All chemical reactions produce heat.
What signs or indicators of chemical changes are shown in these reactions?
Chemical reactions can be obvious. First of all, listen: if you hear any sounds, such as a fizzing sound, that may be one indicator. Another is a change in color, or even state. If a solution is aqueous, and it precipitates (becomes a solid), that's also another indicator of a chemical reaction.
Is slicing an onion a chemical change or a physical change?
Chopping an onion is considered to be a physical process. Chopping an onion is not a chemical process because it does not change the chemical composition.
What evidence tells you that a chemical reaction has occurred?
new substances are formed with new properties.when a object changes its formA chemical reaction has occurred when the chemical identity of a the reactants is different from that of the products. The evidence for this could be obvious or very subtle. For instance, if a colorless gas reacts to form another colorless gas, there would be no visible sign of the reaction. However, often a chemical reaction will cause a change in color or the formation of a solid. The tools you might use to determine if a reaction has taken place depends a great deal on what the suspected reaction is (or what the products formed would be). The most common method is to use analytical chemical technique to verify the presence of the product molecules, or the disappearance of reactant molecules.Note that there are many physical changes that can be confused with chemical changes. For instance, boiling water or freezing water results in many changes in the properties of water, but those are physical changes, not chemical ones. But whether water is liquid, solid or a gas, it is still water, and that is why it is a physical rather than chemical change.See the Related Questions for more information about the difference between chemical and physical changes.(Emperor-A) Here are some evidence they are-A colour changeA gas given offA temperature changethere are 7 ways to spot if a chemical reactions is occurring:1. A Temperature change2. A color change.3. A precipitate is formed (an insoluble substance)4. A gas is given off.5. Light may be given off6. Odor may be given off7. Sound may be given offBasically if there are any permanent changes to the object, such as burning, it can be considered a chemical reaction.Also when there is bubbling or fizzing.A new substance may be createdA change or peak in energy occurs.change in appearance of substance(s)Temperature changePrecipitateColor changeYou can tell when a chemical reaction occurs when there are changes in properties, a color change, and when the changes in properties precipitate.The color change, Fomation of a precipitate, Formation of gas, and Temperature changeEvolution of a gasheat/ energyprecipitate formscolor changeevolution of lightYou could know by the color change, temperature change, a new substance may be created, etc..First it changes into a complete different substanceSecond it changes energyThird it may change colorFourth a solid may appear when two solutions are mixed togetherFifth is a gas might be produced from solids or liquids.the smell and size.kcjajsadThe following observations can help you to determine whether a chemical reaction has occurred:- change of odour (smell)- change of colour- change in temperature, e.g. the production or loss of heat.- change of form, e.g. burning paper- light, heat, or sound is given off.- formation of gases, often appearing as bubbles.- formation of a precipitate (insoluble particles that usually sink to the bottom)- the decomposition of organic matter, e.g. food rotting- evident apparition of a new substance with a new chemical formulaThere are quite a few indicators that a chemical change may have occurred. These include;- Change in color or luster. The release of gas or vapor. (noticeable odor or formation of bubbles) Change in temperature. (either cooling down or heating up) Formation of a precipitate. The release of heat and/or light & sound. A change in volume. The melting point or boiling point changes. A change in electrical conductivity occurs. A change in any distinctive chemical or physical properties occurs. Not all of these changes are necessarily proof of a chemical change, but they are a good indication and a starting point for further investigation. e.g. ruling out physical changes.
What are the not-so-obvious jobs in chemistry?
Train car loader in a chemical plant.
how do people use energy released during chemical changes?
The 2 most common and obvious are: Electricity from batteries. (Photovoltaic cells use physical rather than chemical changes.) Heat from combustion - for heating buildings, industrial processes etc., and in heat-engines (internal-combustion, steam-turbine, gas-turbine, and jet - in former times, hot-air engines and steam engines).
What substance is the byproduct of the chemical equation?
Some chemical equations don't have byproducts. The most obvious one is hydrogen and oxygen. React them and all you get is water. In other equations, there are definitely byproducts...if you were crazy enough to react sodium hydroxide and hydrochloric acid (do this in a fume hood, please) you will get sodium chloride and water. The water would be the byproduct.
