All categories

3 years ago

How can the difference in the brightness of spectral lines be explained

Chemistry

1 answer:

Nikitich [7]3 years ago

3 0

Answer:

The brightness of a line depends on the number of electrons making that transition.

Explanation:

In atomic spectra, some electronic transitions are “forbidden” by the rules of quantum mechanics. That is, <em>some transitions are less probable than others</em>.

The brightness of a given line depends on the number of electrons making that transition.

Allowed transitions will give the brightest lines. The brightness of the other lines will vary depending on how likely the transitions are.

You might be interested in

What type of rock is quartzite

Ilya [14]

Quartzite is a nonfoliated metamorphic rock

6 0

3 years ago

. A compound contains only C, H, N, and O. It contains 37.0 % C and 42.5% O (both by mass), and there are 2 O atoms for every 1

jasenka [17]

Answer:

C₂₁H₁₅N₉O₁₈

Explanation:

Molecular formula is the ratio of atoms that are present in 1 molecule of the compound. We need to find moles of all atoms to find this ratio.

In a basis of 100, moles of C and O are:

<em>Moles C:</em>

37.0 * (1mol / 12g) = 3.083 moles C

<em>Moles O: </em>

42.5g * (1mol / 16) = 2.656 moles O

Now, to find moles of H, we need determine moles of H2O produced:

0.0310g H2O * (1mol / 18g) = 1.72x10⁻³ moles H2O * 2 = 3.44x10⁻³ moles H

These moles were produced when 0.157g of the compound react. In a basis of 100g:

3.44x10⁻³ moles H * (100g / 0.157g) = 2.194 moles H

In the same way, moles of N are:

0.0230g NH3 * (1mol / 17g) = 1.35x10⁻³ moles H2O

These moles were produced when 0.103g of the compound react. In a basis of 100g:

1.35x10⁻³ moles H * (100g / 0.103g) = 1.313 moles N

Empirical formula is (The simplest whole number ratio of atoms presents in a molecule). Dividing in the low number of moles (Moles N):

C: 3.083 moles C / 1.313 moles N = 2.3

O: 2.656 moles O / 1.313 moles N = 2.0

N: 1.313 moles N / 1.313 moles N = 1

H: 2.194 moles H / 1.313 moles N = 1.67

This ratio times 3 (To have the whole number ratio):

C: 7

O: 6

N: 3

H: 5

The empirical formula is:

C₇H₅N₃O₆

And weighs:

C: 7*(12g/mol)= 84

H: 5 * (1g/mol) = 5

N: 3 * (14g/mol) = 42

O: 6* (16g/mol) = 96

227g/mol

As the molecular mass of the compound is 681g/mol:

681 / 227 = 3

The empirical formula times 3 is the molecular formula, that is:

C₇H₅N₃O₆ × 3

4 0

3 years ago

Does anyone know how to do this?

Elanso [62]

Work out each and total up. hope this helped.

8 0

4 years ago

Use the following table to answer the question. Strong acids Weak acids Weak bases Strong bases HBr CH3COOH NH3 NaOH HCl HF NH4O

Y_Kistochka [10]

Answer: The salt which has the highest pH is $CH_3COONa$

Explanation: Salts are formed by the reaction of acid and base. General equation for the generation of salt is given by:

$HX+BOH\rightarrow BX+H_2O$

The given salts are formed from the reaction of acids and bases.

1) $K_2SO_4$

This is a salt formed by the reaction of strong base (KOH) and strong acid $(H_2SO_4)$ . So, this salt is a neutral salt.

$H_2SO_4+2KOH\rightarrow K_2SO_4+2H_2O$

2) $CuSO_4$

This is a salt which is formed by the reaction of weak base $(Cu(OH)_2)$ and strong acid $(H_2SO_4)$ . So, this salt is an acidic salt.

$H_2SO_4+Cu(OH)_2\rightarrow CuSO_4+2H_2O$

3) $NH_4Cl$

This is a salt which is formed by the reaction of weak base $(NH_3)$ and strong acid (HCl). So, this salt is an acidic salt.

$HCl+NH_3\rightarrow NH_4Cl$

4) $CH_3COONa$

This is a salt which is formed by the reaction of strong base (NaOH) and weak acid $(CH_3COOH)$ . So, this salt is a basic salt.

$CH_3COOH+NaOH\rightarrow CH_3COONa+H_2O$

Now, we have to find the salt which has the highest pH value.

Highest pH value means that the salt must be basic in nature and from the given salts, only $CH_3COONa$ is basic salt. Hence, this salt has the highest pH value.

6 0

3 years ago

Read 2 more answers

4. Which of the following statements is true?

Aleksandr [31]

4) The answer is: Chemical reaction rates vary with the conditions of the reaction, but nuclear decay rates do not.

Differences between nuclear and chemical reactions:

1) The electrons of an atom participates in a chemical reaction and protons in nuclear reaction.

2) Chemical reactions involve the rearrangement of electrons, because there is transfer, loss, gain and sharing of electrons in chemical reactions.

3) Nuclear reactions can produce new elements, because number of protons and neutrons is changed, chemical reactions donot produce new element.

4) Chemical reactions require heat or an input of energy to occur, this is activation energy.

5) Isotopes of the same element behave differently in a nuclear reaction, because isotopes have different number of neutrons, so products of a nuclear reaction is different.

6) The answer is: nuclear change.

Transmutation is a process that involves a change in the nucleus of an atom. It can be natural or artificial.

For example: 14/7 N + 4/2 He --> 17/8 O + 1/1 H.

This example is the first artificial nuclear transmutation described by Rutherford in 1919.

Artificial transmutation can be expressed by nuclear reaction:

Target Nuclide + Bombardment Particle → New Nuclide + Ejected Particle.

5 0

3 years ago