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3 years ago

If you look at the periodic table today which elements would best represent a triad as predicted by Dobereiner?

Chemistry

1 answer:

777dan777 [17]3 years ago

8 0

Answer: B. Nickel Copper Zinc

Explanation:

Dobereiner's triads was a group of three elements. Dobereiner said that the relative atomic mass of the middle element in each triad was average of the relative atomic masses of the other two elements.

Thus if A, B and C forms Dobereiner's triads, the mass of B is average of mass of A and C.

A. Hydrogen Oxygen Nitrogen:

mass of oxygen = 15.999

mass of oxygen according to Dobereiner = $\frac{1.008+14.007}{2}=7.5075$

B. Nickel Copper Zinc

mass of copper = 63.5

mass of copper according to Dobereiner = $\frac{58.7+65.38}{2}=62.04$

C. Aluminum Gallium Indium

mass of gallium = 69.72

mass of gallium according to Dobereiner = $\frac{26.98+114.82}{2}=84.39$

D. Neptunium Plutonium Americium

mass of Plutonium = 244

mass of Plutonium according to Dobereiner = $\frac{243+237.04}{2}=240.02$

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Change in boiling point: ΔT =i · Kb · b.

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b - molality, moles of solute per kilogram of solvent., this is also same for both solution, because ther is same amount of substance.

i - Van't Hoff factor.

Van't Hoff factor for sugar solution is 1, because sugar do not dissociate on ions.

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The answer for this question is A

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What is the type of weak bond between the hydrogen of one molecule and the nitrogen of another molecule, where the two don't act

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<h2>Hydrogen Bonding</h2>

Explanation:

Hydrogen bonding is a type of weak bond.
Hydrogen Bonding occurs when the hydrogen atom of one molecule is bonded with a molecule of high electronegativity element like nitrogen of another molecule.
It is a type of dipole-dipole interations.
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4 years ago

The nonvolatile, nonelectrolyte testosterone, C19H28O2 (288.40 g/mol), is soluble in benzene C6H6. Calculate the osmotic pressur

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Explanation:

From the ideal gas equation

P = mRT/MW × V

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T is temperature of benzene solution = 298 K

MW is molecular weight of testosterone = 288.40 g/mol

V is volume of benzene solution = 286 ml = 286 cm^3

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