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Gekata [30.6K]
3 years ago
7

Sarah heated some orange coloured crystals in a test tube. The crystals turned green and fizzed. After the fizzing stopped, the

test tube was allowed to cool. A green powder was left in the tube. Determine whether a chemical or a physical reaction has occurred. Identify two observations that support your decision.
Chemistry
1 answer:
Anni [7]3 years ago
6 0
A chemical change has occurred.
This is indicated by a colour change occurring (from orange to green) as well as a gas being given off (seen as the fizzing). If the fizzing made a small amount of noise, it also indicates that sound energy is given off, which is another indication that a chemical reaction has occurred.
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5 0
3 years ago
A chemist determined by measurements that 0.050 moles of aluminum participated in a chemical reaction. Calculate the mass of alu
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Answer:

13.5 g

Explanation:

This question is solved easily if we remember that the number of moles is obtained by dividing the mass into the atomic weight or molar mass depending if we are referring to elements or molecules.

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8 0
3 years ago
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4 0
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What is the oxidation number of phosphorus (P) in phosphoric acid (H3PO4)?
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Hope that helps!

4 0
3 years ago
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