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3 years ago

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Mendeleev noticed that if he organized the elements by atomic weight certain patterns emerged. For instance, elements in the sam

e group (family) appeared to have the same
A) valence.
B) melting point.
C) isotopic ratio.
D) number of neutrons.

2 answers:

Inga [223]3 years ago

6 0

I've had a similar question on an assignment myself, so I'm going to assume it had the same idea.

When you organize them in such a way, the pattern that emerges tells you elements organized by atomic weight have the same number of valence electrons.

Hope this helps!

lys-0071 [83]3 years ago

5 0

Answer:

Is option A

Explanation:

The correct answer is valence. Our current periodic table puts these elements in the same column on the periodic table. We now know they have the same number of valence electrons.

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Answer:

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Explanation:

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$R_t = R_o[1 + \alpha(T-T_o)]\\\\$

where;

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To is the room temperature

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$R_t = R_o[1 + \alpha(T-T_o)]\\\\\R_t = 1.59*10^{-8}[1 + 0.0038(T-20)]$

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$R_t,_{silver} = 2R_o,_{iron}\\\\1.59*10^{-8}[1 + 0.0038(T-20)] =(2 *9.71*10^{-8})\\\\\ \ (divide \ through \ by \ 1.59*10^{-8})\\\\1 + 0.0038(T-20) = 12.214\\\\1 + 0.0038T - 0.076 = 12.214\\\\0.0038T +0.924 = 12.214\\\\0.0038T = 12.214 - 0.924\\\\0.0038T = 11.29\\\\T = \frac{11.29}{0.0038} \\\\T = 2971.1 \ ^0C$

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Answer:

1)

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where here:

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If we observe the field lines around a magnet, we observe that:

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3)

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It can be applied as follows:

- Direction of index finger = direction of motion of the charge

- Direction of middle finger = direction of magnetic field

- Direction of thumb = direction of the force (for a negative charge, the direction must be reversed)

In this problem:

- Direction of motion = to the right (index finger)

- Direction of field = downward (middle finger)

- Direction of force = into the screen (thumb)

4)

The radius of a particle moving in a magnetic field is given by:

$r=\frac{mv}{qB}$

where here we have:

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$v=2155 m/s$ is the speed of the alpha particle

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6)

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2- A circular motion in the direction perpendicular to the magnetic field

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7)

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8)

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See the last 7 answers in the attached document.

<span class="sg-text sg-text--link sg-text--bold sg-text--link-disabled sg-text--blue-dark"> docx </span>

<span class="sg-text sg-text--link sg-text--bold sg-text--link-disabled sg-text--blue-dark"> pdf </span>

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AveGali [126]

Answer:

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2. 100/12 = 8.3 m/s

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Explanation:

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