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4 years ago

For question #12, use the following picture: 12. What element is this? How do you know?

Chemistry

2 answers:

labwork [276]4 years ago

8 0

Answer: The element shown in the image is Helium (He).

Explanation: We are given a image of an atom having protons, neutrons and electrons.

Number of protons as shown in image = 2

Number of neutrons as shown in image = 2

Number of electron as shown in image = 2

Atomic number = Number of protons = Number of electrons

Atomic number of the element = 2

Atomic Mass = Number of protons + Number of neutrons

Atomic mass = 2 + 2 = 4

The element having Atomic number = 2 and mass number = 4 is Helium.

Element = $^4_2\textrm{He}$

morpeh [17]4 years ago

3 0

I believe the element is Helium. I know this because an atom of helium has an atomic number of 2, meaning it has 2 protons. Because it is an atom of helium and not an ion of helium it also possess the same number of electrons as well which is 2.

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Soloha48 [4]

This can be solved using ideal gas equation:

ideal gas equation,

P\times V=n\times R\times T

Here,

P denotes pressure

V denotes volume

n denotes number of moles of gas

R denotes gas constant

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The values given here are as follows;

T=314 K

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V=11.0 L

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Putting all the values in the above equation,

P=\frac{ 0.703\times 0.0821\times 314}{11.0 }

P=1.64 atm

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3 years ago

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fredd [130]

Answer:

10moles of kcl

Explanation:

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4 years ago

Procaine hydrochloride (MW = 273) is a 2-ion electrolyte, dissociating 80%. Calculate its dissociation factor. Round to tenths p

Inga [223]

Answer:

Dissociation factor = 1.8

Explanation:

Data provided in the question:

Molecular weight of the Procaine hydrochloride = 273

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Fraction Dissociating, α = 80% = 0.8

Now,

the dissociation factor 'i' is given as:

i = 1 + α × ( n - 1 )

on substituting the respective values, we get

i = 1 + 0.8 × ( 2 - 1 )

i = 1 + ( 0.8 × 1 )

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4 years ago