Mention 6 products from coal tar as a result of destructive distillation of coal

Selenium (Se) has 30 protons and 20 neutrons in each atom, therefore its atomic

allochka39001 [22]

Answer:

30, 50

Explanation:

Hello,

In this since an element's atomic number is equal to the number of protons in its atom, we can infer that selenium's atomic number is 30. Moreover, due to the fact the the neutrons are equal to the atomic mass minus the atomic number or the number of protons, by knowing the number of neutrons we compute the atomic as follows:

$neutrons=mass-protons\\\\mass=neutrons+protons\\\\mass=30+20\\\\mass=50a.m.u$

Thus, answer is 30, 50.

Best regards.

8 0

2 years ago

Are properties such as odor, color, density, and solubility physical or chemical properties?

storchak [24]

Physical properties- color, density, solubility.
Chemical property- odor.

You see, a physical property is any property that can be measured , and a one that describes the state of the physical system.

https://socratic.org/questions/are-properties-such-as-odor-color-density-and-solubility-physical-or-...

8 0

3 years ago

Read 2 more answers

Dinitrogen tetraoxide, N2O4, decomposes to nitrogen dioxide, NO2, in a first-order process. If k = 1.5 x 103 s-1 at 5 ºC and k =

Arada [10]

Answer:

The activation energy for the decomposition = 33813.28 J/mol

Explanation:

Using the expression,

$\ln \dfrac{k_{1}}{k_{2}} =-\dfrac{E_{a}}{R} \left (\dfrac{1}{T_1}-\dfrac{1}{T_2} \right )$

Wherem

$k_1\ is\ the\ rate\ constant\ at\ T_1$

$k_2\ is\ the\ rate\ constant\ at\ T_2$

$E_a$ is the activation energy

R is Gas constant having value = 8.314 J / K mol

Thus, given that, $E_a$ = ?

$k_2=4.0\times 10^3s^{-1}$

$k_1=1.5\times 10^3s^{-1}$

$T_1=5\ ^0C$

$T_2=25\ ^0C$

The conversion of T( °C) to T(K) is shown below:

T(K) = T( °C) + 273.15

So,

T = (5 + 273.15) K = 278.15 K

T = (25 + 273.15) K = 298.15 K

$T_1=278.15\ K$

$T_2=298.15\ K$

So,

$\ln \frac{1.5\times 10^3}{4.0\times 10^3}\:=-\frac{E_{a}}{8.314}\times \left(\frac{1}{278.15}-\frac{1}{298.15}\right)$

$E_a=-\ln \frac{1.5\times \:10^3}{4.0\times \:10^3}\:\times \frac{8.314}{\left(\frac{1}{278.15}-\frac{1}{298.15}\right)}$

$E_a=-\frac{8.314\ln \left(\frac{1.5\times \:10^3}{4\times \:10^3}\right)}{\frac{1}{278.15}-\frac{1}{298.15}}$

$E_a=-\frac{689483.53266 \ln \left(\frac{1.5}{4}\right)}{20}$

$E_a=33813.28\ J/mol$

The activation energy for the decomposition = 33813.28 J/mol

8 0

2 years ago

The density of an object depends on what? Answer correctly and quick!

Dennis_Churaev [7]

Answer:

Density of a quantity of matter is its mass divided by its volume. The mass of an object depends on the atomic mass of the individual atoms or molecules and the how close the they are compressed together.

Explanation:

8 0

2 years ago

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Copper atoms are used to produce pennies. The copper atoms in pennies share many electrons. Pennies contain

kaheart [24]

Answer:

Metallic bonds

Explanation:

Metallic bonds joins atoms of metals and atoms of alloys together. The copper used in making pennies is a metallic substance so it contains metallic bonds.

The formation of this bond type is predicated on the large atomic radius, low ionization energy and large number of electrons in the valence shell.
The bond is an attraction between the positive nuclei of all closely packed atoms in the lattice and the electron cloud.
The electron cloud is jointly formed by all the atoms by losing their outermost shell electrons.

This way the bond in pennies are metallic in nature.

5 0

2 years ago