How did the work of Dmitri Mendeleev differ from that of John Newlands in the development of the periodic table?

1 answer:

3 0

When Newlands tried to create a periodic table, his tried to conform to the "Rule of Octaves" he had discovered. He had the right idea, in that if you arrange the elements by atomic weight there would be similarities every 7 elements (not 8 because noble gases hadn't been discovered yet) but he tried to push this rule so much that he would put multiple elements in the same box to try to keep the rule. Mendeleev, however, left gaps in this table for undiscovered elements, which paved the way for our modern periodic table.

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A proton travels at a speed of 2.0 × 106 meters/second. Its velocity is at right angles with a magnetic field of strength 5.5 ×

Finger [1]

So here we are given that the the velocity of the proton ( V ) is 2.0 × $10^6$ meters / second, with a magnetic field of strength 5.5 × $10^{-3}$ tesla. If they each form a right angle, they are hence perpendicular to one another, such that ....

F = q( V × B ),

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AVprozaik [17]

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The standard enthalpy of formation of Ca2+ (g) (∆H = 1934 kJ/mol)

Alex73 [517]

Answer:

see explanation

Explanation:

The process of ionization to produce cations is endothermic. For formation of Ca⁺² two ionization steps need be illustrated as follows...

1st ionization step: Ca° + 590Kj => Ca⁺ + e⁻

2nd ionization step: Ca⁺ + 1151Kj => Ca⁺² + e⁻

__________________________________-

Net Ionization Rxn: Ca° + 1741Kj => Ca⁺² + 2e⁻

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MA= output force/input force
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MA= 50

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1.53 moles of Fe is your solution hope it helps!

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