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3 years ago

I need to know which piece of research in the square was done by John Dalton.

Chemistry

1 answer:

sashaice [31]3 years ago

8 0

Answer:

C. atomic mass

Explanation:

John Dalton was a very versatile man. His work is important in physics, meteorology, medicine (description of color blindness) and chemistry. He was included in researching of partial pressures and atomic theory. He proposed one of the first models of atom in the beginning of 19th century.

He published a table where he proposed relative atomic weight of six atoms. In his honor, standardized unit for atomic weight is called dalton (Da) and weighs 1/12 of carbon atom weight.

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But the Wannsee and answer is c

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3 years ago

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Elena-2011 [213]

Answer:

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According to reaction, 1 mole of CaO is produced along with 1 mole of carbon-dioxide.

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3 years ago

A 0.65 M solution of an unknown amine base is found to be 2.2% ionized at equilibrium. Calculate the value for Kb for this amine

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The value of Kb of the unknown amine is 3.22 x 10^-4.

Weak electrolytes:

The compound which do not dissociate completely when added to the aqueous solution are called weak electrolytes. The electrolyte and its ions exists in equilibrium. In case of weak base, the equilibrium constant is expressed as Kb.

Calculations:

Step 1:

The percentage of amine ionized at equilibrium is 2.2%.

NH3 + H2O ------> NH4+ + OH-

The concentration of conjugate acid at equilibrium is calculated as:

2.2 = (x/0.65) x 100

x = 0.0143 M

Step 2:

The equilibrium constant (Kb) is calculated as:

Kb = x^2/0.65 - x

= (0.0143)^2/(0.65 - x)

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Learn more about weak electrolytes here:

brainly.com/question/19340043

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2 years ago

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dem82 [27]

Answer:

carbon is a -4 anion

Explanation:

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3 years ago

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I need to know which piece of research in the square was done by John Dalton. ​

I need to know which piece of research in the square was done by John Dalton.