Which is a characteristic of atoms?

For the quantum number lower case L = 0, how many possible values are there for the quantum number m subscrip l?

hram777 [196]

Quantum number L, angular quantum number, describes the shape of the orbitals. Reliable sources show that the quantum number l = 0 will give an orbital of spherical shape, polar if l = 1, and cloverleaf if l = 2.

The third quantum number is m which is is used to denote the magnetic quantum number. This describes the orientation of a certain orbital in shape. This quantum number can take the values of -l to l. Thus, the only value for m in this case is 0. m = 0.

Quantum numbers are used to describe the position of the electrons in the orbitals.

3 0

3 years ago

A combination of salt and sugar grains is best classified as a mixture because...

MatroZZZ [7]

I think b I don’t k it bc there was a black screen uo there

6 0

3 years ago

Research is being carried out on cellulose as a source of chemicals for the production of fibers, coatings, and plastics. Cellul

Luden [163]

Answer:

+ 636 KJ

Explanation:

We want to arrive to the equation

C6H12O6(s) ---------> 6 H2CO(g) ΔH ° rxn = ?

by manipulating algebraically the first four given equations.

We notice the first one has our product H2CO(g) as a reactant. This indicates we must take the inverse of that equation. Also we need 6 mol of H2CO(g), thus it also needs to be multiplied by 6

6 CO2(g) + 6 H2O(g) ------->6H2CO(g) + 6O2(g) ΔH °comb = + 572.9 KJ/x 6

Now we want C6H12O6(s) as a reactant and it is a product in the second one, therefore lets reverse it

C6H12O6(s) -------> 6 C(s) + 6 H2(g) + 3 O2(g) ΔH ° f = + 1274.4 KJ/mol

Now if take the third equation and multiply it by six we will cancel the C(s) with the above equation

6 C(s) + 6O2(g) ---------> 6 CO2(g) ΔH ° f = - 393.5 KJ/mol x 6

Finally by multiplying the last equation by 6 and adding all the equations we will arrive at our desired one

6 H2(g) + 3 O2(g) -----------> 6H2O(g) ΔH ° f = - 285.8 KJ/mol x 6

then lets add them to get ΔH ° rxn:

6 CO2(g) + 6 H2O(g) ------->6H2CO(g) + 6O2(g) ΔH °comb = + 3437.4 KJ

+ C6H12O6(s) -------> 6 C(s) + 6 H2(g) + 3 O2(g) ΔH ° f = + 1274.4 KJ

+ 6C(s) + 6O2(g) ---------> 6 CO2(g) ΔH ° f = - 2361.0 KJ

+6 H2(g) + 3 O2(g) -----------> 6H2O(g) ΔHº f = - 1714.8 KJ

C6H12O6(s) ---------> 6 H2CO(g)

ΔH ° rxn = 3437.4 + 1274.4 - 2361.0 - 1714.8 = 636 KJ

8 0

3 years ago

Tentukan pH Mg(OH)2 jika ke dalam larutan MgCl2 0,2M ditambahkan NH4OH sehingga

Vadim26 [7]

Answer:

pH 8.89

Explanation:

English Translation

If the MgCl₂ solution of 0.2 M has its pH raised by adding NH₄OH, the precipitate will begin to form at a pH of approximately.

Given the solubility product (Ksp) of Mg(OH)₂ = 1.2 x 10⁻¹¹

Assuming all of the salts involved all ionize completely

MgCl₂ ionizes to give Mg²⁺ and Cl⁻

MgCl₂ ⇌ Mg²⁺ + 2Cl⁻

1 mole of MgCl₂ gives 1 moles of Mg²⁺

Since the concentration of Mg²⁺ is the same as that of MgCl₂ = 0.2 M

Mg(OH)₂ is formed from 1 stoichiometric mole of Mg²⁺ and 2 stoichiometric moles of OH⁻

Ksp Mg(OH)₂ = [Mg²⁺][OH⁻]²

(1.2 x 10⁻¹¹) = 0.2 × [OH⁻]²

[OH⁻]² = (6×10⁻¹¹)

[OH⁻] = √(6×10⁻¹¹)

[OH⁻] = 0.000007746 M

p(OH) = - log [OH⁻] = - log (0.000007746)

pOH = 5.11

pH + pOH = 14

pH = 14 - pOH = 14 - 5.11 = 8.89

Hope this Helps!!!

3 0

3 years ago

Methanol (methyl alcohol, CH₃OH), is a very important industrial chemical. Formerly, methanol was prepared by heating wood to hi

katrin [286]

Answer:

CO(g) + 2H₂(g) → CH₃OH(l)

Explanation:

Carbon monoxide has molecular formula CO, molecular hydrogen has formula H₂, and methanol is CH₃OH.

The reactants are CO and H₂ and the product CH₃OH:

CO(g) + H₂(g) → CH₃OH(l)

To balance the equation, the elements must have the same amount on each side. C and O are balanced, but there is 4H in the product and only 2 in the reactant, so we multiply H₂ for 2:

CO(g) + 2H₂(g) → CH₃OH(l)

And the equation is balanced.

4 0

3 years ago