Answer:
Explanation:
First we need to find how many moles of ammonium weigh 62 grams.
Molar mass of NH4 = (14.0)+(4*1.0) grams
or 18.0 grams/mole
62 (g)/18(g/mole) = 3.444... moles of NH4
If it is dissolved in 5 litres of water, the concentration will be 3.444moles/5L
or 0.6888 M.
Answer:
pKb = 10.96
Explanation:
Tartaric acid is a dyprotic acid. It reacts to water like this:
H₂Tart + H₂O ⇄ H₃O⁺ + HTart⁻ Ka1
HTart⁻ + H₂O ⇄ H₃O⁺ + Tart⁻² Ka2
When we anaylse the base, we have
Tart⁻² + H₂O ⇄ OH⁻ + HTart⁻ Kb1
HTart⁻ + H₂O ⇄ OH⁻ + H₂Tart Kb2
Remember that Ka1 . Kb2 = Kw, plus pKa1 + pKb2 = 14
Kb2 = Kw / Ka1 → 1×10⁻¹⁴ / 9.20×10⁻⁴ = 1.08×10⁻¹¹
so pKb = - log Kb2 → - log 1.08×10⁻¹¹ = 10.96
Answer:
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The nucleus controls and regulates the activities of the cell (e.g., growth and metabolism) and carries the genes, structures that contain the hereditary information. Nucleoli are small bodies often seen within the nucleus.
Explanation:
Answer:
8 moles
Explanation:
When we are asked to convert from grams of a substance into moles, we have to use the substance's molar mass.
Meaning that for this problem, we'll <em>use the molar mass of hydrogen peroxide</em> (H₂O₂), as follows:
There are 8 moles in 272 grams of hydrogen peroxide.