The fraction of the original amount remaining is closest to 1/128
<h3>Determination of the number of half-lives</h3>
- Half-life (t½) = 4 days
- Time (t) = 4 weeks = 4 × 7 = 28 days
- Number of half-lives (n) =?
n = t / t½
n = 28 / 4
n = 7
<h3>How to determine the amount remaining </h3>
- Original amount (N₀) = 100 g
- Number of half-lives (n) = 7
- Amount remaining (N)=?
N = N₀ / 2ⁿ
N = 100 / 2⁷
N = 0.78125 g
<h3>How to determine the fraction remaining </h3>
- Original amount (N₀) = 100 g
- Amount remaining (N)= 0.78125 g
Fraction remaining = N / N₀
Fraction remaining = 0.78125 / 100
Fraction remaining = 1/128
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Answer is: Na₂SO₄ (sodium sulfate).
The solubility of sodium sulfate increases up to 32.38°C and than decreases at higher temperatures, the solubility becomes almost independent of temperature.
At 32.38°C it releases of crystal water and melting of the hydrated salt.
Sodium sulfate is the white, inorganic compound.
Sodium sulfate is highly soluble in water.
Taking into account the reaction stoichiometry, 1 mole of silver chromate Ag₂CrO₄ are produced in this reaction.
<h3>Reaction stoichiometry</h3>
In first place, the balanced reaction is:
2 AgC₂H₃O₂ + K₂CrO₄ → Ag₂CrO₄ + 2 KC₂H₃O₂
By reaction stoichiometry (that is, the relationship between the amount of reagents and products in a chemical reaction), the following amounts of moles of each compound participate in the reaction:
- AgC₂H₃O₂: 2 moles
- K₂CrO₄: 1 mole
- Ag₂CrO₄: 1 mole
- KC₂H₃O₂: 2 moles
<h3>Moles of Ag₂CrO₄ formed</h3>
By reaction stoichiometry 2 moles of AgC₂H₃O₂ form 1 mole of Ag₂CrO₄.
In other words, according to this balanced chemical equation, 1 mole of silver chromate Ag₂CrO₄ are produced in this reaction.
Learn more about the reaction stoichiometry:
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Unfortunately the data provided doesn't include the DENSITY of the ammonium chloride solution and molarity is defined as moles per volume. So without the density, the calculation of the molarity is impossible. But fortunately, there are tables available that do provide the required density and for a 20% solution by weight, the density of the solution is 1.057 g/ml.
So 1 liter of solution will mass 1057 grams and the mass of ammonium chloride will be 0.2 * 1057 g = 211.4 g. The number of moles will then be 211.4 g / 53.5 g/mol = 3.951401869 mol. Rounding to 3 significant digits gives a molarity of 3.95.
Now assuming that your teacher wants you to assume that the solution masses 1.00 g/ml, then the mass of ammonium chloride will only be 200g, and that is only (200/53.5) = 3.74 moles.
So in conclusion, the expected answer is 3.74 M, although the correct answer using missing information is 3.95 M.
Answer:
the correct choice would be: 4. Reaction rates are not related to spontaneity.
Explanation:
The speed of reaction is independent of spontaneity, since it depends on other factors such as the amount of reagent.
The amount of reagent is one of the variables that most influences the speed of reaction, the greater the amount of reagent, the faster the reaction will be and thus the speed will be increased.