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Why might a substance have less mass after a chemical change than it had before?
Wiki User
∙ 16y ago
After a chemical reaction, some of the bonds have been broken, and some new bonds have been formed. So, that's how a substance is changed after the reaction.
Lupe Hahn
Wiki User
∙ 16y agoA substance will never actually have less mass after a chemical change that it did before. The Law of Conservation of Mass specifically states that in a chemical reaction, no mass is lost nor gained. In many cases though, some form of the final product is released into the air, and can therefore not be measured as part of the final product. For example, when a log burns and turns to ash, the ash weigh less than the initial log. This is only because gas was produced when the log burned, and was let off into the air. But if you managed to somehow contain all the ash and gas together, it would have exactly the same mass as the log. So really, if a substance seems to have less mass after a chemical change than before, it is because you aren't seeing the entire final substance.
Wiki User
∙ 11y agoA substance can have less mass after a nuclear reaction (with radioactivity) but not with a chemical reaction. Lavoisier would be cursing you in his grave.
Wiki User
∙ 14y agoThe law of conservation of mass states that mass cannot be created or destroyed. This is why the mass is the same before and after a chemical reaction.
Wiki User
∙ 15y agoIt changes after most chemical reactions because the reactants change.
Wiki User
∙ 13y agoNo. Mass and Energy are always conserved in chemical reactions.
Wiki User
∙ 14y agomass is changed to energy via the famous E = mc^2 equation. The mass lost in a chemical reaction is so small, it would be tough to measure but theoretically it is not zero.
Wiki User
∙ 6y agoReactans are transformed in products, another types of molecules.
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Is mixing acid with base a chemical or physical change?
Adding a base to an acid or vice versa in changing the chemical properties of that solution. In both cases you are neuralizing the solution. There might be a physical change as well, but it would depend on what chemicals where mixing. But this reaction will definitely have a chemical change.
Which of the following is a definite indicator that a chemical change has occured?
Definite indicators of a chemical reaction include exothermic reactions (heat), colour change, bubbles and there might be a few morea new substance forms (study island)
How would you determine if a chemical change has occurred?
There are a few ways... 1) the identity of the substance changed 2) there was a gas released (fizzing, bubbles, etc.) 3) color change (even though color change is a physical property, it might be caused by a chemical reaction)
What changes during chemical change?
In a Chemical Change, atoms rearrange to form one or more new substance. They do this by breaking bonds and forming new ones.The identity of the substance undergoing the change is altered. In short: it depends on the chemical change.You would see a gas given off, the colour might change and it may change states that can not be turned back to what it was.hope I've answered your questio :)During a chemical change, the properties change and a new substance is formed. Temperatures change, colors change or smoke is present, and/or gas/bubbles are releasedA new substance is created and heat, light, or gasses are given off.Even though the persons answer is very well explained (down below) but I think you are looking for a more simple answer which is: Burning PaperA new chemical is formed. Evidence of this is cooling or heating of the samples as well as bubbles meaning a gas is formed.Vinegar and baking soda form a gas and it bubbles.Forms different substance.
When two substances are mixed they might form a new substance What would indicate that a new substance has been formed?
Some indicators of a chemical reaction are: - change of color - change of odor - release of a gas - change of the temperature - change of the viscosity - formation of a precipitate - change of general appearance - possible explosion - possible chemiluminiscence - formation of new compounds
Is gas considered a chemical substance?
It might, or it could just be vaporization of the substance (physical change).
What Three Things can happen when a Chemical Reaction occur?
A chemical reaction can change a substance into a solid, liquid, or gas. It may cause a substance to explode or could cause no change at all.
Must a new substance be formed when you observe a chemical property?
Yes , it should or else it is a physical property
What type of property of a pure substance describes how that substance might from a new substance?
this describes a chemical property
Is mixing acid with base a chemical or physical change?
Adding a base to an acid or vice versa in changing the chemical properties of that solution. In both cases you are neuralizing the solution. There might be a physical change as well, but it would depend on what chemicals where mixing. But this reaction will definitely have a chemical change.
Which of the following is a definite indicator that a chemical change has occured?
Definite indicators of a chemical reaction include exothermic reactions (heat), colour change, bubbles and there might be a few morea new substance forms (study island)
Does a chemical change always produce heat?
adding heat to a substance might produce a new gas, resulting in a chemical change for example when baking powder is heated it produces carbon dioxide gas which is needed to make a cake fluffy and light.
How would you determine if a chemical change has occurred?
There are a few ways... 1) the identity of the substance changed 2) there was a gas released (fizzing, bubbles, etc.) 3) color change (even though color change is a physical property, it might be caused by a chemical reaction)
What happens to the composition of a substance during a chemical change?
Atoms are rearranged, heat may be given off, changes in color and odor might occur, or a gas or precipice may be formed. The composition is changed, and the above are signs of a chemical change.
What changes during chemical change?
In a Chemical Change, atoms rearrange to form one or more new substance. They do this by breaking bonds and forming new ones.The identity of the substance undergoing the change is altered. In short: it depends on the chemical change.You would see a gas given off, the colour might change and it may change states that can not be turned back to what it was.hope I've answered your questio :)During a chemical change, the properties change and a new substance is formed. Temperatures change, colors change or smoke is present, and/or gas/bubbles are releasedA new substance is created and heat, light, or gasses are given off.Even though the persons answer is very well explained (down below) but I think you are looking for a more simple answer which is: Burning PaperA new chemical is formed. Evidence of this is cooling or heating of the samples as well as bubbles meaning a gas is formed.Vinegar and baking soda form a gas and it bubbles.Forms different substance.
What is matter with a definite chemical make up?
it might be substance
a change in the chemical properties of substance results in a?
A substance can take on three physical states: Solid, liquid, or gas. The main physical changes from a thermodynamic standpoint are the amount of entropy(disorder) of the molecules of the substance. Density, temperature, volume are also characteristically different at each physical state and can be used to manipulate compounds between the three.
