All categories

1 year ago

Use MO diagrams to place B2+, B2, and B2- in order of (a) decreasing bond energy; (b) decreasing bond length.

1 answer:

3 0

We use the MO diagram for a homonuclear diatomic species (since C and N are neighbours, we treat them as the "same").

The first two electrons contribute to bonding. The next two are anti-bonding.

The next six contribute to bonding, and the following six are anti-bonding.

So, if we start with CN+, which has 4+5-1 (8) valence electrons, we note that the first two electrons contribute to bonding, while the next two cancel this out; the next four contribute to bonding, so the bond order is 4/2 = 2.

If we add one more electron to get CN, there are now 5 bonding electrons, giving bond order 5/2=2.5.

Adding one more to give CN- would give the bond order 6/2 = 3. (If we added more electrons, each one would lower the bond order.)

Given a series of molecules with identical skeletal structures, the one with the highest bond order has the highest bond energy:

CN+ < CN < CN-

Lewis structures will verify that CN- has a triple bond, but they do not work particularly well for CN+ and CN.

learn more about bond orders at

brainly.com/question/9713842

#SPJ1

You might be interested in

Indicate which reaction will occur faster. explain your reasoning. select the single best answer. solvolysis of 1−chloro−2,2−dim

Radda [10]

The tert-butyl chloride in ethanol would surely react faster than the solvolysis of 1-chloro-2,2-dimethyl propane. It is known that both reactions are under the SN2 category so it would be hard for these reactions to occur. However, SN1 reactions are possible because of the ethanol which is a polar solvent. Both would form carbocations but tert-butyl chloride forms a more stable carbocation while the 1-chloro-2,2-dimethyl propane forms a primary carbocation only.

6 0

3 years ago

Place the following elements in order of increasing electronegativity.K Cs PA. K < P < CsB. P < Cs < KC. Cs < K &

skad [1K]

Answer:

C. Cs < K < P

Explanation:

Electronegativity is the basically the tendency of an atom to attract electrons. The pauling scale is used to quantify electronegativity, the most electronegative element; fluorine has a value of 4.0 and francium, the least electronegative element has a value of 0.7

The electronegative values of the following elements are given as;

K = 0.82

Cs =0.79

P = 2.19

Arranging in order of increasing electronegativity, we have;

Cs < K < P. The correct option is;

C. Cs < K < P

5 0

3 years ago

The osmotic pressure of a solution containing 2.04 g of an unknown compound dissolved in 175.0 mLof solution at 25 ∘C is 2.13 at

kherson [118]

Answer: The molecular formula of the compound is $C_4H_{10}O_4$

Explanation:

To calculate the concentration of solute, we use the equation for osmotic pressure, which is:

$\pi=iMRT$

Or,

$\pi=i\times \frac{\text{Mass of solute}\times 1000}{\text{Molar mass of solute}\times \text{Volume of solution (in mL)}}\times RT$

where,

$\pi$ = osmotic pressure of the solution = 2.13 atm

i = Van't hoff factor = 1 (for non-electrolytes)

Given mass of compound = 2.04 g

Volume of solution = 175.0 mL

R = Gas constant = $0.0821\text{ L atm }mol^{-1}K^{-1}$

T = temperature of the solution = $25^oC=[273+25]=298K$

Putting values in above equation, we get:

$2.13atm=1\times \frac{2.04\times 1000}{\text{Molar mass of compound}\times 175.0}\times 0.0821\text{ L.atm }mol^{-1}K^{-1}\times 298K\\\\\text{Molar mass of compound}=\frac{1\times 2.04\times 1000\times 0.0821\times 298}{2.13\times 175.0}=133.9g/mol$

Calculating the molecular formula:

The chemical equation for the combustion of compound having carbon, hydrogen and oxygen follows:

$C_xH_yO_z+O_2\rightarrow CO_2+H_2O$

where, 'x', 'y' and 'z' are the subscripts of carbon, hydrogen and oxygen respectively.

We are given:

Mass of $CO_2=36.26g$

Mass of $H_2O=14.85g$

We know that:

Molar mass of carbon dioxide = 44 g/mol

Molar mass of water = 18 g/mol

For calculating the mass of carbon:

In 44 g of carbon dioxide, 12 g of carbon is contained.

So, in 36.26 g of carbon dioxide, $\frac{12}{44}\times 36.26=9.89g$ of carbon will be contained.

For calculating the mass of hydrogen:

In 18 g of water, 2 g of hydrogen is contained.

So, in 14.85 g of water, $\frac{2}{18}\times 14.85=1.65g$ of hydrogen will be contained.

Mass of oxygen in the compound = (22.08) - (9.89 + 1.65) = 10.54 g

To formulate the empirical formula, we need to follow some steps:

Step 1: Converting the given masses into moles.

Moles of Carbon = $\frac{\text{Given mass of Carbon}}{\text{Molar mass of Carbon}}=\frac{9.89g}{12g/mole}=0.824moles$

Moles of Hydrogen = $\frac{\text{Given mass of Hydrogen}}{\text{Molar mass of Hydrogen}}=\frac{1.65g}{1g/mole}=1.65moles$

Moles of Oxygen = $\frac{\text{Given mass of oxygen}}{\text{Molar mass of oxygen}}=\frac{10.54g}{16g/mole}=0.659moles$

Step 2: Calculating the mole ratio of the given elements.

For the mole ratio, we divide each value of the moles by the smallest number of moles calculated which is 0.659 moles.

For Carbon = $\frac{0.824}{0.659}=1.25\approx 1$

For Hydrogen = $\frac{1.65}{0.659}=2.5$

For Oxygen = $\frac{0.659}{0.659}=1$

Converting the mole fraction into whole number by multiplying the mole fraction by '2'

Mole fraction of carbon = (1 × 2) = 2

Mole fraction of oxygen = (2.5 × 2) = 5

Mole fraction of hydrogen = (1 × 2) = 2

Step 3: Taking the mole ratio as their subscripts.

The ratio of C : H : O = 2 : 5 : 2

The empirical formula for the given compound is $C_2H_5O_2$

For determining the molecular formula, we need to determine the valency which is multiplied by each element to get the molecular formula.

The equation used to calculate the valency is:

$n=\frac{\text{Molecular mass}}{\text{Empirical mass}}$

We are given:

Mass of molecular formula = 133.9 g/mol

Mass of empirical formula = 61 g/mol

Putting values in above equation, we get:

$n=\frac{133.9g/mol}{61g/mol}=2$

Multiplying this valency by the subscript of every element of empirical formula, we get:

$C_{(2\times 2)}H_{(5\times 2)}O_{(2\times 2)}=C_4H_{10}O_4$

Hence, the molecular formula of the compound is $C_4H_{10}O_4$

4 0

3 years ago

Plz answer all 3, I will give 5 stars and brainiest!!! :) THANKS

Cerrena [4.2K]

Answer:

B. Positive charge is caused by lack of electrons. A positive ion is formed by the loss of negatively charged electrons. Although the number of protons does not change in the ion, there is an excess number of protons over electrons which produces the positive charge. All electrons in the outer energy level are lost.

C. If there are more electrons than protons, then the element is a negative ion. The amount of neutrons does not play a factor into making a difference between an atom or an ion.

Explanation:

please give brainliest. :)

and have a great day!

5 0

3 years ago

An a transition metal with 91 protons and electrons?

ser-zykov [4K]

Protactinium

Hshsbsbwhwhhsnsnanananananababsbsbsbsbsbsbababjaajajajnsnsnsnana

6 0

3 years ago

Read 2 more answers