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What are four types of evidence that indicate that a chemical reaction may have taken place?
Wiki User
∙ 8y ago
1. A colour change occurs
2. A gas is evolved.
3. A precipitate is formed.
4. A large energy change occurs.
Wiki User
∙ 8y ago
- Change in temperature: If the temperature of the reactants increases or decreases significantly.
- Formation of a precipitate: A solid substance formed when two liquids react.
- Change in color: Observing a change in color before and after the reaction.
- Evolution of gas: Gas bubbles forming or a gas being released during the reaction.
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What evidence do you have that a chemical reaction took place?
Evidence of a chemical reaction includes the formation of a new substance with different properties, changes in color, the release of gas or heat, or the formation of a precipitate. Additionally, changes in mass due to the rearrangement of atoms in the reactants can also indicate a chemical reaction has occurred.
If you are trying to decide whether a chemical reaction does or does not take place when two substances are mixed what kind of evidence will you look for?
To determine if a chemical reaction takes place when two substances are mixed, you can look for evidence such as color change, formation of precipitate, gas production, change in temperature, and the evolution of light or sound. These observable changes indicate a chemical transformation has occurred.
Does no visible change mean no chemical reaction?
Not necessarily. A lack of visible change does not always indicate the absence of a chemical reaction. Some reactions may be occurring at a molecular level and not produce a noticeable alteration in appearance. It's important to consider other evidence, such as changes in temperature, gas production, or pH level, to determine if a chemical reaction has taken place.
What is the evidence that a chemical reaction took place when zinc mixed with HCl?
Evidence that a chemical reaction took place when zinc mixed with HCl includes the production of hydrogen gas bubbles, formation of zinc chloride as a product, and an increase in temperature of the reaction mixture due to the exothermic nature of the reaction. Additionally, the disappearance of the solid zinc as it undergoes dissolution is another indication that a chemical reaction has occurred.
When burning a piece of wood what evidence is there to show that a chemical reaction had taken place?
Evidence of a chemical reaction when burning wood includes the release of heat and light, as well as the production of ash and smoke. Changes in the physical properties of the wood, such as color, texture, and shape, also indicate a chemical transformation has occurred. Additionally, the formation of new substances like carbon dioxide and water vapor during the burning process further confirms a chemical reaction has taken place.
What changes gives NO evidence that a chemical reaction has taken place?
Physical changes give no evidence that a chemical reaction has taken place, because no chemical reaction has taken place.
What evidence is there to show that a chemical reaction has taken place when an egg is cooked?
The change in color indicates that a chemical reaction has taken place.
What evidence that a chemical reaction has taken place would a living thing show?
work
What is an example of a color change that does not indicate a chemical reaction?
Many materials can change colour according to the temperature without there being any chemical reaction taking place.
What are the uses of chemical formulas?
The uses of chemical formulas are mainly to show how the various elements are in any compound. This will indicate how a particular chemical reaction takes place.
What evidence was there that a chemical reaction was taking place in the decomposition of hydrogen peroxide?
Evidence of a chemical reaction in the decomposition of hydrogen peroxide includes the formation of oxygen gas bubbles, a change in temperature (exothermic reaction), and the color change of the solution. Additionally, the release of oxygen gas could be tested by using a glowing splint, which would reignite in the presence of oxygen.
What evidence do you have that a chemical reaction took place?
Evidence of a chemical reaction includes the formation of a new substance with different properties, changes in color, the release of gas or heat, or the formation of a precipitate. Additionally, changes in mass due to the rearrangement of atoms in the reactants can also indicate a chemical reaction has occurred.
How can you be sure that at least one chemical change has occurred?
Evidence that a chemical reaction has taken place usually include appearance of a precipitate, change in color, or production of a gas.
What form of evidence do you need to show that a chemical reaction has taken place?
You must video tape it and make sure the final result is either a physical change or a chemical change.
What is the evidence that a chemical reaction took place when silver nitrate was mixed with ammonium chloride?
The evidence that a chemical reaction took place when silver nitrate was mixed with ammonium chloride is the formation of a white precipitate of silver chloride. This indicates that a chemical reaction occurred between the silver ions from silver nitrate and the chloride ions from ammonium chloride, resulting in the insoluble silver chloride. Additionally, the solution may turn cloudy or there may be a color change, further supporting the occurrence of a chemical reaction.
What is the evidence that a chemical reaction took place when zinc mixed with HCl?
Evidence that a chemical reaction took place when zinc mixed with HCl includes the production of hydrogen gas bubbles, formation of zinc chloride as a product, and an increase in temperature of the reaction mixture due to the exothermic nature of the reaction. Additionally, the disappearance of the solid zinc as it undergoes dissolution is another indication that a chemical reaction has occurred.
What is the reaction when zinc reacts with sulphuric acid?
When zinc reacts with sulfuric acid, zinc sulfate and hydrogen gas are produced. The chemical equation for the reaction is: Zn + H2SO4 → ZnSO4 + H2.
