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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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Which element, when combined with Iodine, would most likely form an ionic compound?
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In the given options:

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How many moles of Cu do you need to react with 12 moles of O2?<br> 2Cu(s) + O2(g) 2CuO(s)
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Answer:

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General Formulas and Concepts:

<u>Chemistry</u>

  • Stoichiometry

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<u>Step 1: Define</u>

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<em>We are given 2 sig figs.</em>

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3 0
3 years ago
Để pha 2 lít dung dịch H2SO4 0,1N từ axit đặc 98% (d 1.84g/ml). Cần lấy bao nhiêu ml acid đặc
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Answer:

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Explanation:

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