The distance between two singly ionised atoms is 1 angstrom if the charge on both ions

The force between two alpha particles separated by a distance r is f.in order to have same force f the distance between singly ionized chlorine atoms separated by a distance of 1. 2 r2.4 r3 . r / 24 . r / 4

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Updated April 28, 2018

By Jack Brubaker

When metals and nonmetals form compounds, the metal atoms donate electrons to the nonmetal atoms. The metal atoms become positive ions due to their loss of negatively charged electrons, and the nonmetal atoms become negative ions. Ions exhibit attractive forces for ions of opposite charge -- hence the adage that “opposites attract.” The force of attraction between oppositely charged ions follows Coulomb’s law: F = k * q1 * q2 / d2, where F represents the force of attraction in Newtons, q1 and q2 represents the charges of the two ions in coulombs, d represents the distance between the ions’ nuclei in meters and k is a proportionality constant of 8.99 x 109 Newton square meters per square coulomb.

Refer to a table of ions to find the charges of the positive and negative ions in the compound. Chemical formulas, by convention, list the positive ion first. In the compound calcium bromide, or CaBr2, for example, the calcium represents the positive ion and exhibits a charge of +2. Bromine represents the negative ion and exhibits a charge of -1. Therefore, q1 = 2 and q2 = 1 in the Coulomb’s law equation.

Convert the charges on the ions to coulombs by multiplying each charge by 1.9 x 10-19. The +2 calcium ion therefore exhibits a charge of 2 * 1.9 x 10-19 = 3.8 x 10-19 coulombs, and bromine exhibits a charge of 1.9 x 10-19 coulombs.

Determine the distance between the ions by referring to a table of ionic radii. When they form solids, ions normally sit as close to each other as possible. The distance between them is found by adding together the radii of the positive and negative ions. In the example calcium bromide, Ca2+ ions exhibit a radius of about 1.00 angstroms and Br- ions exhibit a radius of about 1.96 angstroms. The distance between their nuclei is therefore 1.00 + 1.96 = 3.96 angstroms.

Convert the distance between the ions’ nuclei to units of meters by multiplying the value in angstroms by 1 x 10-10. Continuing the previous example, the distance of 3.96 angstroms converts to 3.96 x 10-10 meters.

Calculate the force of attraction according to F = k * q1 * q2 / d2.

Using the previously obtained values for calcium bromide and using 8.99 x 109 as the value for k gives F = (8.99 x 109) * (3.8 x 10-19) * (1.9 x 10-19) / (3.96 x 10-10)2. Under the rules of the scientific order of operations, the squaring of the distance must be carried out first, which gives F = (8.99 x 109) * (3.8 x 10-19) * (1.9 x 10-19) / (1.57 x 10-19). Performing the multiplication and division then gives F = 4.1 x 10-9 Newtons. This value represents the force of attraction between the ions.

Tips

Numbers such as 1.9 x 10-19 represent scientific notation. In this case, the number reads as “one point nine times ten to the negative nineteenth power.” You can easily enter these values into a scientific calculator using the scientific notation button, usually labeled EE.

Text Solution

the two circles touch each other the two circles do not touch each other the circle described by the singly-ionized charge will have a radius double that of the other circle both the ions will go along circles of equal radii.

Answer : A::C

Solution : When a charged particle is subjected to a perpendicular magnetic field, it will describe a circular path of radius, `r=mv//Bq` i.e. `rprop1//(q//m)`. Thus option (c) is true. As time period of revolution, `T=(2pim)/(Bq)` is independent of v and r, so the particle will return to its initial position after one revolution, hence the two particles of different charges will return to their initial positions after one revolution and their paths will touch each other there.

Text Solution

`2.3xx10^(-8)N``4.6xx10^(-8)N``1.5xx10^(-8)N`None of these

Answer : A

Solution : Change on electron `16xx10^(-19)C` Using the relation, `F=(1)/(4pi epsilon_(0)).(q_(1)q_(2))/(r^(2))` `"Here, "q_(1)=q_(2)=1.6xx10^(-19)C` `r=1Å=10^(-10)m` So, Force between the electrons `F=(9xx10^(9)xx(1.6xx10^(-19))^(2))/((10^(-10))^(2))=2.3xx10^(-8)N`

Answer

Verified

Hint: The electric dipole moment is calculated by using formula-$P = qD$where $q$ is the magnitude of the charge$P$ is the dipole moment$D$ is the separation between two chargesBy putting the values in their respective places, we can easily get the value for the dipole moment.

Complete step by step answer:

When two equal and opposite charges $ + q$ and $ - q$ respectively are separated by a fixed distance then this combination is called Electric Dipole. The midpoint of both the charges $ + q$ and $ - q$ respectively is called the center of the dipole.The product of the magnitude of the charge on the dipole and separation between two charges is called the electric dipole moment. The electric dipole moment is a vector quantity and is denoted by vector $\overrightarrow P.$The direction of the dipole moment is from a negative charge to a positive charge. This sign convention is only followed in Physics. In Chemistry, this sign convention is taken opposite, that is, from positive charge to negative charge. The line with the direction of the electric dipole is called the axis of dipole.Now, to find the dipole moment having magnitude of charge $1.6 \times {10^{ - 19}}$ and at separation $1$ angstromAccording to question, it is given that$q = 1.6 \times {10^{ - 19}}$$D = 1\dot A = {10^{ - 10}}m$Therefore, putting these values in the formula-$P = qD \\\Rightarrow P = 1.6 \times {10^{ - 19}} \times {10^{ - 10}}C - m \\\Rightarrow P = 1.6 \times {10^{ - 29}}C - m \\ $

Therefore, the electric dipole moment is $1.6 \times {10^{ - 29}}C - m$. Hence, the correct answer is option (B).

Note:

Electric dipoles are also prominent in chemistry. In many molecules, the center of positive and negative charges coincide at some point due to which distance between two charges is zero. The examples of such molecules are carbon dioxide and methane. This is called non-polar molecules. Polar molecules are just the opposite of non-polar molecules.