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3 years ago

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Chemistry

1 answer:

Vanyuwa [196]3 years ago

5 0

Answer:

NaCl and water: Ion - Dipolo forces

NaCl and Hexane: Ion-ion force between Na+ and Cl− ions and London dispersion force between two hexane molecules

Explanation:

NaCl and water:

The ion-dipole force is established between an ion and a polar molecule. Polar molecules are dipoles, they have a positive end and a negative end.

H2O has an important charge separation in its atoms (the H has a positive partial charge and the O has a negative partial charge) and this causes permanent electrical dipoles in the water molecules.

Sodium chloride is an ionic compound formed of positive and negative charge ions, Na + and Cl-. Depending on their charge, these ions will be attracted to opposite charges in the water molecules (H attracts chloride ions and O attracts sodium ions), causing the salt to dissolve in water.

NaCl and Hexane:

The dispersion forces of London occur between apolar molecules, and they occur because when two molecules approach a distortion of the electronic clouds of both originates, generating in them, transient induced dipoles, due to the movement of the electrons, so it allows interact with each other.

Hexane is a non-polar molecule, which are those that have no charge separation within the molecules. Then there is London dispersion force between two hexane molecules. 

On the other hand, the ion-ion force is produced between ions of the same or different charge, where ions with charges of opposite sign attract each other and ions with charges of the same sign repel each other. This is the force that occurs between the NaCl ions.

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Answer: A solution with a pH of 7 must be neutral.

Explanation:

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If the temperature of 15 grams of water changes from 21C to 24C, how many joules of heat were involved? Show work

goblinko [34]

Answer:

189 Joules

Explanation:

Applying,

Q = cm(t₂-t₁)............. equation 1

Where Q = Heat, c = specific heat capacity of water, m = mass of water, t₁ = Initial Temperature, t₂ = Final temperature.

From the question,

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2 years ago

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tia_tia [17]

Answer : The cell potential for this reaction is 0.50 V

Explanation :

The given cell reactions is:

$Pb^{2+}(aq)+Zn(s)\rightarrow Zn^{2+}(aq)+Pb(s)$

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Oxidation half reaction (anode): $Zn\rightarrow Zn^{2+}+2e^-$

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$E_{cell}$ = cell potential for the reaction = ?

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Now put all the given values in the above equation, we get:

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Alexus [3.1K]

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