Answer:
seneca
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Answer:
During MITOSIS, the parent, diploid (2n), cell is divided to create two identical, diploid (2n), daughter cells. ... After cytokinesis, the ploidy of the daughter cells remains the same because each daughter cell contains 4 chromatids, as the parent cell did.
Answer:
pH = 2.69
Explanation:
The complete question is:<em> An analytical chemist is titrating 182.2 mL of a 1.200 M solution of nitrous acid (HNO2) with a solution of 0.8400 M KOH. The pKa of nitrous acid is 3.35. Calculate the pH of the acid solution after the chemist has added 46.44 mL of the KOH solution to it.</em>
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The reaction of HNO₂ with KOH is:
HNO₂ + KOH → NO₂⁻ + H₂O + K⁺
Moles of HNO₂ and KOH that react are:
HNO₂ = 0.1822L × (1.200mol / L) = <em>0.21864 moles HNO₂</em>
KOH = 0.04644L × (0.8400mol / L) = <em>0.0390 moles KOH</em>
That means after the reaction, moles of HNO₂ and NO₂⁻ after the reaction are:
NO₂⁻ = 0.03900 moles KOH = moles NO₂⁻
HNO₂ = 0.21864 moles HNO₂ - 0.03900 moles = 0.17964 moles HNO₂
It is possible to find the pH of this buffer (<em>Mixture of a weak acid, HNO₂ with the conjugate base, NO₂⁻), </em>using H-H equation for this system:
pH = pKa + log₁₀ [NO₂⁻] / [HNO₂]
pH = 3.35 + log₁₀ [0.03900mol] / [0.17964mol]
<h3>pH = 2.69</h3>
Answer:
A. Na₂SO₄ and HCl
C. Polar solutes are soluble in polar solvents but are insoluble in non-polar solvents Non-polar solutes are insoluble in polar solvents but are are soluble in non-polar solvents
Ionic solutes are soluble in polar solvents but are insoluble in non-polar solvents.
Like dissolves like simply means that molecules of substances having similar chemical properties dissolve in each other
Explanation:
A. Ionic substances like Na₂SO₄ are composed of charged particles called ions. These ions are either positively charged or negatively charged, therefore, they are attracted to substances of opposite charges. Also, polar molecules like HCl contains two oppositely charged ends. A polar solvent consists of molecules with two oppositely charged ends, therefore, ionic substances as well polar substances dissolve in them according to the concept of like dissolves like.
Gasoline being non-polar will only dissolve in like substances, polar solvents.
C. Polar solutes are soluble in polar solvents but are insoluble in non-polar solvents Non-polar solutes are insoluble in polar solvents but are are soluble in non-polar solvents
Ionic solutes are soluble in polar solvents but are insoluble in non-polar solvents.
The statement "Like dissolves like" simply means that molecules of substances having similar chemical properties dissolve in each other. For example gasoline, a non-polar substance will dissolve only in a non-polar solvent like kerosene. Also, HCl, a polar molecule will dissolve in a polar solvent like water.
