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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
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What evidence was there that a chemical reaction was taking place in the decomposition of hydrogen peroxide?
The decomposition of H2O2 is exothermic and oxygen is released.
What evidence do you have that a chemical reaction took place?
changes in its appearance ie colour and state
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 is the evidence that a chemical reaction took place when zinc mixed with HCl?
Yes, and zinc chloride and hydrogen are obtained.
What is the evidence that a chemical reaction took place when silver nitrate was mixed with ammonium chloride?
A white precipitate of silver chloride (AgCl) is formed.
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?
The decomposition of H2O2 is exothermic and oxygen is released.
What evidence do you have that a chemical reaction took place?
changes in its appearance ie colour and state
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?
A white precipitate of silver chloride (AgCl) is formed.
What is the evidence that a chemical reaction took place when zinc mixed with HCl?
Yes, and zinc chloride and hydrogen are obtained.
What is the reaction when zinc reacts with sulphuric acid?
We can see bubbles of gas being released. The gas is a new substance, so this is evidence that a chemical reaction is taking place. the gas released during this reaction is hydrogen.
