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2 years ago

Quis critérios foram usadps por dobereiner em sua tentava de organiza os elementos químicos?

Chemistry

1 answer:

anyanavicka [17]2 years ago

8 0

Döbereiner grouped the known elements into triads (sets of three) so that

• The atomic mass of the middle element was approximately the average of the other two

• The chemical properties of the middle element were between those of the other two

• The physical properties of the middle element were between those of the other two

One example of a triad is Li – Na – K.

(a) Atomic mass of Na = 23.0 u

Average atomic mass of Li and K = (6.9 u + 39.1 u)/2 = 46.0 u/2 = 23.0 u

(b) Li reacts slowly with water. Na reacts rapidly. Potassium reacts violently.

Average melting point of Li and K = (454 °C + 330 °C)/2 = 784 °C/2

= 392 °C

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snow_lady [41]

Thank you for posting your question here at brainly. Below is the solution:

moles HClO4 = 0.100 L x 0.18 M = 0.018
moles LiOH = 0.030 L x 0.27 = 0.0081
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total volume = 0.130 L
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vesna_86 [32]

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2 years ago

Describe the composition of humus and why it is an effective organic fertilizer.

asambeis [7]

Answer:

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samira-

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Hunter-Best [27]

Answer:

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Explanation:

Hello,

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