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VARVARA [1.3K]
3 years ago
15

John dalton postulated several statements about the atom. which statement did he NOT state?

Chemistry
1 answer:
algol [13]3 years ago
7 0

Answer:

The atom is divisible particle and can be subdivided into smaller particles proton, neutron and electrons was not stated by John dalton.

Explanation:

The postulate of Dalton's atomic theory  that atom is indivisible particle and can not be subdivided into smaller particles was later changed because atom can be divided into neutrons, protons and electrons.

Electron:

The electron is subatomic particle that revolve around outside the nucleus and has negligible mass. It has a negative charge.

Symbol= e⁻

Mass= 9.10938356×10⁻³¹ Kg

It was discovered by j. j. Thomson in 1897 during the study of cathode ray properties.

Proton and neutron:

While neutron and proton are present inside the nucleus. Proton has positive charge while neutron is electrically neutral. Proton is discovered by Rutherford while neutron is discovered by James Chadwick in 1932.

Symbol of proton= P⁺

Symbol of neutron= n⁰  

Mass of proton=1.672623×10⁻²⁷ Kg

Mass of neutron=1.674929×10⁻²⁷ Kg

All these three subatomic particles construct an atom. A neutral atom have equal number of proton and electron.

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Explanation:

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Answer:

The empirical formula is SF6 (option E)

Explanation:

Step 1: Data given

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Step 2: Calculate moles

Moles = mass /molar mass

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</span><span>
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8) I think that the most important points which best show </span><span>how the addition of a solute affects the boiling point, the freezing
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9) </span>[H+][OH-]= Kw = 1.0 * 10^-14
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10) Since the formula of the given acid is HA it undergoes like that :<span> HA<=> H+ + A- .
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Now we have only </span>[H+] and to go further you need to write  <span>electroneutrality equation for the reaction :
</span>[H+] = [OH-] + [A-]  (since [H]>>>[OH]), then 
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