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.
(2) 40. mL at 80.°C (4) 80. mL at 40.°C
B. liquids.
C. solids.
D. fluids.
E. none of the above
Convection is the transfer of heat in a fluid (which can be a liquid or gas) through the movement of its particles. A fluid near a heat source will get heated, causing it to rise and exchange place with the cooler, denser fluid.
Energy transfer by convection is primarily restricted to both liquids and gases, which are both classified as fluids. Hence, the correct answer is D. Fluids.
Convection refers to heat transfer in a gas or liquid by the circulation of currents from one region to another. This happens when a fluid near a heat source gets heated, its particles move faster and spread apart, causing the fluid to become less dense. As a result, the warmer, less dense fluid rises, and the cooler, denser fluid sinks. The continuous movement of fluid in this way creates what we call a convection current, which results in the transfer of energy.
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(2) melting of copper
(3) condensation of ethanol vapor
(4) sublimation of iodine
Answer:
The correct answer is option 3.
Explanation:
Condensationof ethanol vapors is an exothermic process. This is because particles in gaseous has highest energy . Some of this energy gets released when these particles or ethanol vapors condenses into a liquid state where they have less amount of energy in comparison to gaseous state.
As we know that exothermic reaction are those reaction in which heat is released into the surroundings.
Where as the other options are example of an endothermic reaction.where heat is absorbed from the surroundings.
Hence, the correct answer is option 3.
b. C
c. Si
d. P
Answer: Option (a) is the correct answer.
Explanation:
A metal is a substance which loses electron(s) in order to attain stability.
For example, sodium is an alkali metals with atomic number 11 and its electronic distribution is 2, 8, 1.
So, in order to attain stability sodium will readily lose 1 electron and forms ion.
Whereas non-metals are the substances which gain electron(s) in order to attain stability.
For example, atomic number of carbon is 6 and its electronic configuration is 2, 4.
To attain stability a carbon atom shares it 4 valence electrons with another atom.
Thus, we can conclude that out of the given options, Na is a metal.
B) decomposition
C) single replacement
D) double replacement
The reaction in which two or more substances combine to form one substance is called a synthesis reaction, Option A is the correct answer.
The reaction in which two or more molecules combine to form one or more different molecule is called a synthesis reaction.
These are also called as Combination Reaction.
Example Synthesis reaction of Ammonia from Hydrogen and Nitrogen , known as Haber's Process.
3H₂ + N₂-----> 2NH₃
This reaction takes place at high temperature and pressure.
Therefore , The reaction in which two or more substances combine to form one substance is called a synthesis reaction, Option A is the correct answer.
To know more about Synthesis Reaction
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