1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
krok68 [10]
3 years ago
14

Explain how different observations and experiments led to changes in the atomic model.

Chemistry
1 answer:
Bingel [31]3 years ago
4 0

> Explain how different observations and experiments led to changes in the atomic model.

The atomic model has progressed over time. As scientists have learned more about the atoms, the atomic model has changed.

Democritus: first proposed that matter cannot be divided into smaller pieces

Dalton: created the 1st atomic theory. He viewed atoms as tiny solid balls

JJ Thomson: discovered electrons, he showed that atoms are made of even smaller things

Rutherford: discovered protons and nucleus, he showed that atoms have positive particles in the center and that atoms are made up mostly of empty space

Bohr: improved Rutherford’s model by proposing that electrons move around the nucleus in layers or shells

Chadwick: discovered neutrons = particles with no charge

The modern model of the atom is made up of works collaborated since 1920 which has electrons moving around the nucleus in a cloud.

> Explain how line spectra are used to identify elements and what they indicate about atoms.

Actually each element has its own unique spectra, hence this property can be used to identify the element. The line spectra give us an indication about the energy levels of the electrons, and each wavelength produces different colors.

> Represent electron arrangements using electron configuration, orbital notation, shorthand notation, and Lewis dot notation.

To answer your question, I will illustrate an example. The s orbital can accommodate 2 electrons, p orbital can accommodate 6, d orbital can accommodate 10, f orbital can accommodate 14. To take as example, Mg contains 12 electrons using the Aufbau principle, the electron configuration is: 1s2 2s2 2p6 3s2 the numbers after the letter represent the amount of electrons, the letters (s, p) represent the sublevel of the electron, while the number before the letter represent the principal quantum number, or "level".

Apply the rules and limitations of each quantum number to identify possible and impossible quantum number sets.

>There are four quantum numbers.

1. Principal quantum number (n) can take values of any positive whole numbers

2. Angular momentum quantum number (l) is from 0 to n – 1

3. Magnetic quantum number (ml) is from –l to +l

4. Spin quantum number (ms) only takes two values, positive spin and negative spin: +1/2, -1/2

From these rules you can identify possible and impossible set of quantum numbers.

You might be interested in
When one atom of carbon reacts with two atoms of oxygen, they combine to form one molecule of carbon dioxide. How many atoms of
tankabanditka [31]

The equation is: C+O2=>CO2

Since we got 10 molecules of CO2 new balanced equation would be 10C+10O2=>10CO2

from this equation we can see that we have 10 molecules of oxygen, however ,we need to find atoms. There are 2 atoms in the oxygen molecule so we need to multiply 10 by 2 which gives us 20 atoms.

The answer: there are 20 atoms of oxygen

4 0
3 years ago
The acid-dissociation constants of HC3H5O3 and CH3NH3+ are given in the table below. Which of the following mixtures is a buffer
sergey [27]

Answer:

A mixture of 100. mL of 0.1 M HC3H5O3 and 50. mL of NaOH

Explanation:

The pH of a buffer solution is calculated using following relation

pH=pKa+log(\frac{salt}{acid} )

Thus the pH of buffer solution will be near to the pKa of the acid used in making the buffer solution.

The pKa value of HC₃H₅O₃ acid is more closer to required pH = 4 than CH₃NH₃⁺ acid.

pKa = -log [Ka]

For HC₃H₅O₃

pKa = 3.1

For CH₃NH₃⁺

pKa = 10.64

pKb = 14-10.64 = 3.36 [Thus the pKb of this acid is also near to required pH value)

A mixture of 100. mL of 0.1 M HC3H5O3 and 50. mL of NaOH

Half of the acid will get neutralized by the given base and thus will result in equal concentration of both the weak acid and the salt making the pH just equal to the pKa value.

8 0
2 years ago
Are ions of alkali metals larger or smaller than ions of alkaline earth metals from the same period
PtichkaEL [24]
Because size of an atom INCREASES from top to bottom and DECREASES from left to right on the periodic table. If to elements are in the same period they can't increase in size based on the up or down trend. Instead, notice that Alkali Metals are LEFT of Alkaline Earth Metals. Therefore, the Alkali Metal will be larger than the Alkaline Earth Metals.
7 0
3 years ago
Why are measurements important for science?<br> Give two reasons.<br> Please help meeee :(
stepladder [879]

Answer:

-Being in the service of quality, safety, designing and problem solving.

-It plays an importnat part in our lives too, to measure any surface, object, etc.

Explanation:

Measurement is perhaps one of the most fundamental concepts in science. Without the ability to measure, it would be difficult for scientists to conduct experiments or form theories.

4 0
2 years ago
Which state(s) of matter do not have a definite shape nor volume? A. Liquids only B. Liquids and gases C. Gases only D. Gases an
Evgen [1.6K]
<h2>Answer:</h2>

C. Gases only

<h3>Explanation:</h3>

Gases are the state of matter that has no definite shape and volume while liquids have no definite shape but have definite volume and solids have both definite shape and definite volume. so the correct option is "C".

5 0
3 years ago
Other questions:
  • This is part two of the other questions
    13·1 answer
  • Which formula correctly represents the product of an reaction between ethane and chlorine
    13·1 answer
  • The reaction in which hydrogen and oxygen are produced by running an electric current through water is an example of
    8·2 answers
  • how many milliliters of a stock solution of 2.00M KNO3 would you need to prepare 100.0mL of 0.150M KNO3?
    15·1 answer
  • 11. How did the solubility product constant Ksp of KHT in pure water compare to its solubility product constant Ksp of KHT in KC
    6·1 answer
  • Draw the major product formed when the following epoxide reacts with methanol in the presence of sulfuric acid. Use wedge/dash b
    7·1 answer
  • a laboratory procedure calls for making 510.0 mL of a 1.6 M KNO3 solution. How much KNO3 in grams is needed
    8·1 answer
  • How can the properties of a substance be used to identify it?
    8·1 answer
  • PLS I WILL GIVE BRAINLY How do the number of violence electrons of the light metals compared to those heavier than boron
    8·1 answer
  • If an isotope of oxygen has 8 protons, 10 neutrons, and 8 electrons, its mass number is_______.
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!