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Dmitry_Shevchenko [17]
3 years ago
15

What is revealed in the reaction ca2+(aq) + 2oh-(aq) ca(oh)2(s), deltah + 16.71?

Chemistry
2 answers:
ch4aika [34]3 years ago
8 0
The given reaction has a positive value of enthalpy change which means that it is an endothermic reaction. The heat energy flows into the reaction as it proceeds. So, to allow this reaction to occur heat should be supplied to the substances.
Veronika [31]3 years ago
8 0

The reaction is endothermic - apex


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Why is a homogeneous mixture not considered a pure substance? Question 6 options: A pure substance can be separated by physical
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<u><em>Answer:</em></u>

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2. What is true if mass is conserved in a reaction?

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  • There are equal numbers of atoms on both sides.

3. <em>Methane reacts with oxygen then what are the products?</em>

<u><em>Answer:</em></u>

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4. Which one of the following is not a homogeneous mixture?

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5. The substance is not uniform in appearance and each part of the mixture contains a combination of different ingredients in different ratios.

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6. If a solution is saturated, which of these is true?

<u><em>Answer:</em></u>

  • More solvent can be dissolved

7. Which of these substances are molecules?

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8. What makes a solution a homogeneous mixture?

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9. When a solute is added to a solution, why does it remain homogeneous?

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11. <em>How many chlorine (Cl) atoms would be in 4 molecules of salt (4 NaCl)?</em>

<u><em>Answer:</em></u>

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12. <em>In a solution of salt and water, which component is the solute?</em>

<u><em>Answer:</em></u>

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<u><em>Answer:</em></u>

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14. If you have 5 grams of product after a chemical reaction, how many grams of reactants did you have at the start of the reaction?

<em>Answer:</em>

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15. What is the difference between a compound and a mixture?

<u><em>Answer:</em></u>

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16. A firework exploding would be an example of a(n) ________.

<u><em>Answer:</em></u>

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17. If Lavoisier heated 100 grams of powdered mercuric oxide to produce 93 grams of liquid mercury, how much oxygen would be released?

Solution

                       2HgO ==> 2Hg + O2

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Moles = mass/molar mass = 0.46 moles

From balance chemcial equation

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<em><u>Solution</u></em>

                         12g Fe + 64g S → _____ g FeS

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                              12 + 64 = 76 g of FeS


Hope this Help.

 





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