Answer:
- Part a) 0.0104 moles copper(II) nitrate.
i) 0.0418 mole Cu
ii) 0.0209 mol Ag NO₃
Explanation:
<u>1) Balanced chemical reaction (single replacement):</u>
In a single replacement reaction a more acitve metal (Cu) replaces a less active metal (Ag)
- Cu + 2 Ag NO₃ → Cu (NO₃)₂ + 2 Ag
<u>2) Mole ratio: </u>
- 1 mole Cu : 2 mole Ag NO₃ : 2 mole Ag
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<u>3) Moles of Ag</u>
- n = mass in grams / atomic mass
- atomic mass of Ag: 107.868 g/mol
- n = 2.25 g / 107.868 g/mol = 0.0209 mol Ag
<u>4) Moles of copper(II) nitrate:</u>
- Set the proportion using the mole ratio:
- 2 mole Ag / 1 mole Cu (NO₃)₂ = 0.0209 mole Ag / x
- Solve: x = 0.0209 / 2 mole Cu (NO₃)₂ = 0.0104 moles Cu(NO₃)₂
That is the answer of part a: 0.0104 moles copper(II) nitrate.
<u>5) Moles of each reactant</u>
i) Cu:
- Set a proportion using the theoretical mole ratio
1 mole Cu / 2 mole Ag = x / 0.0209 mol Ag
- Solve for x: x = 0.0209 / 2 mole Cu = 0.0418 mole Cu
ii) Ag NO₃
- Set a proportion using the teoretical mole ratio
2 mole Ag NO₃ / 2 mole Ag = x / 0.0209 mole Ag
- Solve for x: x = 0.0209 mol Ag NO₃
The most common reaction that causes spoilage isn't a reaction at all. Molds and Bacteria are attracted to the easily found presence of water in the fruit. They find a natural place to reproduce and what they do causes spoilage.
Very few sources talk about the chemical changes that take place. If you put fruit in a refrigerator it slows the spoiling process down. That means that the chemical reaction has to be endothermic (it requires heat to occur)
The process of spoilage is speeded up by bananas for example, giving up Ethylene gas. You do not want to put a banana with tomatoes, because tomatoes are very sensitive to Ethylene. (It's OK to eat them together. They make a terrific salad. Yum).
I cannot find a definitive source that connects all this together, but the conduct of the fruit in refrigerators confirms what I am saying.
Spoilage is a very complex reaction and interaction with the environment. I have given you a hint of what happens but you should search it out to convince yourself of the outcome.
Hi!
When Silver Oxide (Ag20) is heated, it decomposes into Silver and Oxygen.
Answer:
C) 0.800 mol
Explanation:
In order to <u>convert from moles of Al₂O₃ into moles of Al</u>, we'll need to use<em> the stoichiometric coefficients</em>, using a conversion factor that has Al₂O₃ moles in the denominator and Al moles in the numerator:
- 0.400 mol Al₂O₃ *
= 0.800 mol Al
So the correct answer is option C).
Hello!
When finding the chemical formula of a compound, we will need to find the charges of each element/bond.
Looking at our period table, sodium has a +1 charge, written as Na 1+, and sulfate has a charge of -2, and it is written as SO4 2-.
Now, we need to make the charges equivalent. To do this, we need to "criss-cross" the charges. This means that sodium will need to additional atoms to make the charges equal, and sulfate will need one.
Therefore, the chemical formula for sodium sulfate is: Na2SO4.
