Which conversion of energy always occurs in a voltaic cell?

What kinds of information does a structural formula reveal about the compound it represents

stiv31 [10]

Answer:

In organic chemistry, the structural formula shows the bonding and general layout of the molecule.

Explanation:

It can also help in naming the molecule, as many compounds with the same molecular formula have different structural formulas, for example cycloalkanes and alkenes, or aldehydes and ketones.

It tells us about the constituents of the compound, or in other words, the functional groups present. This enables us to predict what kind of properties the compound has and what kind of reactions it can undergo.

It can also help us determine the stereochemistry (shape and spatial orientation) of the compound. This is especially important in organic chemistry and organic chemstry, since certain important reactions will proceed if and only if a molecule with the right shape is employed.

6 0

3 years ago

D) does not dissociate in solution.

natima [27]

Answer:

According to the proton theory of acids and bases by J. Brønsted and T. Lowry, the acid is proton donor.

Explanation:

According to the Bronsted lowry concept an acid is substance that gives protons or hydrogen ion while,

Base is substance that accept hydrogen ion or proton.

Consider the following example:

NH₃ + HCl → NH₄⁺ + Cl⁻

In this example HCl is Bronsted lowry acid it gives H⁺ while ammonia is Bronsted lowry base because it accept H⁺.

This also gives the concept of conjugate acid and base. In given example Cl⁻ is conjugate base of HCl while NH₄⁺ is conjugate acid of ammonia.

4 0

3 years ago

The solubility of nitrogen gas at 25 degrees C and 1 atm is 6.8 x 10^(-4) mol/L. If the partial pressure of nitrogen gas in air

Zolol [24]

Answer:

5.2 x 10⁻⁴ M.

Explanation:

The relationship between gas pressure and the concentration of dissolved gas is given by Henry’s law:

P = kC

where P is the partial pressure of the gaseous solute above the solution.

k is a constant (Henry’s constant).

C is the concentration of the dissolved gas.

At two different pressures, there is two different concentrations of dissolved gases and is expressed in a relation as:

P₁C₂ = P₂C₁,

P₁ = 1.0 atm, C₁ = 6.8 x 10⁻⁴ mol/L.

P₂ = 0.76 atm, C₂ = ??? mol/L.

∴ C₂ = (P₂C₁)/P₁ = (0.76 atm)(6.8 x 10⁻⁴ mol/L)/(1.0 atm) = 5.168 x 10⁻⁴ mol/L ≅ 5.2 x 10⁻⁴ M.

5 0

3 years ago

How does air bubbles affect density of a solid object?

kirill [66]

it decreases the density of the object the air bubbles take up space. it increases the volume of the object slightly but the objects weight remains the same, hence the objects density decreases

6 0

3 years ago

Suppose a laboratory wants to identify an unknown pure substance. The valence electrons of the substance's atoms feel an effecti

zalisa [80]

Answer:

The answer is the third option in the list: It would have smaller atomic radii than Si and higher ionization energies than Si.

Explanation:

The effective nuclear charge is that portion of the total nuclear charge that a given electron in an atom feels.

Since, the inner electrons repel the outer electrons, the effective nuclear charge of a determined electron is the sum of the positive charge (number of protons or atomic number) that it feels from the nucleus less the number of electrons that are in the shells that are are closer to the nucleus than the own shell of such (determined) electron.

Mathematically, the effective nuclear charge (Zeff) is equal to the atomic number (Z) minus the amount (S) that other electrons in the atom shield the given (determined) atom from the nucleus.

Zeff = Z - S.

Since, the valence electrons are the electrons in the outermost shell of the atom, you can find certain trend for the value Zeff.

Let's look at the group to which Si belongs, which is the group 14. This table summarizes the relevant data:

Element Z Group # valence electrons S Zeff = Z - S

C 6 14 4 6 - 4 = 2 6 - 2 = +4

Si 14 14 4 14 - 4 = 10 14 - 10 = +4

Ge 32 14 4 32 - 4 = 28 32 -28 = +4

Sn 50 14 4 50 - 4 = 46 50 - 46 = +4

Pb 82 14 4 82 - 4 = 78 82 - 78 = +4

With that, you have shown that the valence electrons of the unknown substance's atoms feel an effective nuclear charge of +4 and you have a short list of 4 elements which can be the unknown element: C, Ge, Sn or Pb.

The second known characteristic of the unknown substance's atoms is that it has a higher electronegativity than silicon (Si).

So, you must use the known trend of the electronegativity in a group of the periodic table: the electronegativity decreases as you go down in a group. So, three of the elements (Ge, Sn, and Pb) have lower electronegativity than Si, which has left us with only one possibility: the element C. The valence electrons of carbon (C) atoms feel an effective nuclear charge of +4 and it carbon has a higher electronegativity than silicon.

Other two periodic trends attending the group number are the atomic radii and the ionization energy.

The atomic radii generally increases as you go from top to bottom in a group. This is because you are adding electrons to new higher main energy levels. So, you can conclude that the originally unknwon substance (carbon) has a smaller atomic radii, than Si.

The ionization energies generally decreases as you go from top to bottom in a group. This os due to the shielding effect: as seen, the effective nuclear charge of the atom's valence electrons remains constant, while the distance of the electrons from the nucleus increases (the valence electrons are farther away from the nucleus), which means the upper the element in a given group, the larger the ionization energy of the atoms.

With this, our conclusions about the unnkown substance are:

Since it has a higher electronegativity value than silicon (Si), it is right up of Si, and there is on only element possible element than can be (C).

Since, it is upper than silicon (Si), it would have smaller atomic radii.

Due to the shielding effect, it would have larger ionization energies.

The answer is the third option in the list: It would have smaller atomic radii than Si and higher ionization energies than Si.

6 0

3 years ago