Section 1 chapter 4 chem

What did rutherford not explain?

How the negativly charged particles electrons are distibiuted in the space surrounding its positevly charged nucleus

It was known that electrons and protons

Attract each other so what stopped them electrons and the positevly charged nucleus to attact one another?

In the ealier twentieth century a new atomic model evolved as a result of?

The absorbtion and immision of oight by mass

The studies provided a relationship between

Light and an atoms electrons

Which led to

This new understanding led directly to a revolution view of nature of energy and mater and the atomic structure

Before 1900 they thought light only acted

As a wave

It was later discovered that it has

Particle like characteristics

When did the theory of light start?

At the beggining of the twentieth century

Visible light is a kind of?

Electromagnetic radiation

Electromagnetic radiation is?

Its a form of eneergy that has wave like behaviour as it travels through space

Kinds of electromagnetic

X rats ultra violet infared light micro waves and radio waves

All the forms of electromagnetic spectrum form?

The electromagnetic spectrum

All forms of electromagnetics move at a constant speed of

C= 3 × 10^8 m/s

Through?

A vacum

Why through a vacum?

Beacuse air is mostly space

And 3 × 10^8 is also?

Lightbapproximate speed through air

The significant feature Of wave motion is its?

Its repititive nature

Which that repetitive nature can be characterized by

Measurable properties

Which those measurbales are?

Wave length and frequency

Wave length

Its the distance between crest to crest

The unit for wave length is

Meter or nano meter

The unit of frequency is?

( V)

Is defined as the number of waves that pass a guven point in a specific time usualy one second which is?

Frequency

One wave per a second is?

Expressed as hertz

Which is named from?

Heinrich hertz

Frequencies and wave lengths are mathmatically

Related to one another

For electromagnetic radiation there relationship is

C = wavelength x frequency

Beacuse the C is allways the same that means

Frequency and wave lengths are constant

Frequency and wave lengths relationshio to one another?

Are inversly proportional

The two areas that the eyes can see are?

400-700 nanometers

Which is red orange yellow green blue and violet its between ultra violet and infared lights

In the early 1900 scintests made two expirements involving

Interactions of matter and light that could not be explained by the wave theory of light

Photo electric effect

Is the emmision of electrons when light shine son ametal

What was the mystery

the frequency of the light stricking the metal

For metals no electrons were emmited if ?

The light’s frequency was under a minimum amount

Which was regardless of what?

The intensity of the light

Light is known as a form of?

Energy

It can break tpdown the loss electrons of?

Metals

The wave theory of light stated that

At any frequency it can eject an electron from an metal but the scientists were dum founded when why they needed a mnimum frequency in order for the photo electric effect to occur

The explanation of the photo electric effect was found in?

1900

When who was doing what?

When max planck was studying the emmision if light by hot objects

He stated that

The electromagnetic waves are sent out continuously but it should have if the light was only wave like

Which then he stated that electromagnetic waves are sent out by specific small packets called?

Quanta

Quantum

Is the minimum amount of energy that can be gained or lost by an atom

Which he stated

E = hv

Which e h v is?

E is the energy in joule of a quantum of radiation and v is the frequency in s and h is a constant which is known as sth eplankcs constant

Plancks conatsnt is?

6.626 × 10^-34

In 1905 who made plankcs idea bigger and state dwhat?

Albert ipeinstien and tate that electro magnetic radiations consists of dual wave particle nature

While light has many wave like properties it can also be?

Through a stream of particlesm

Each particle holds a

Quantum of energy

He called those particles ?

Photons

A photon

Is a particle of electromagnetic radiation that has zero mass but carries a quantum of energy

The energy of a particular photon depends on the

Frequency of the radiation

How did einstien explain the photoelectic effect

electromagnetic radiation is absorbed by matter only in whole numbers if photons

For an electron to get out of its place

The photon ha sto have enoeugh enrgyto make the electron loose

Acording to the equation

The least amount of energy needed for corresponds to the minimums frequency

Electrins of different eleements are

Bound less or more tightly

So that means

Different metals need diffrent smount of frequencies for the electrons to be knocked outn

When current is passed through a gas at low temperature

The potential energy of the gas atoms increases

Ground state

The lowest energy state of an atom

Exited state

A state where an atom has higher potential energy that it has than ground state

There are many types of?but in the same element they are?

Excited states

The same between atoms

When an exited atom returns to its

Ground state it gives of energy in the form of electromagnetic radiation

When investigators passed a electroc current through the vacum tube containing hydrogen gas at low temperatures they saw?

A pinkish glow

When a narrow beam of light emitted was shine dthrough a prism it showed us

4 specific colors

The four band sof colors were known as the

Emmision line spectrum

Additional series were found in the which soectrum of the hydrogen?

Unktra violet and infrared regions

Which are called which series?

Lymen balmer and paschen series

The clasical theory stated?

That any amount of energy added to the hydrogen causes it to enter exited state

Which means?

That the scientests were especting an the emmision of ontinues range of frequencies of electromagnetic radiation known as the continuty theory

Why did the hydrogens only give a specific frequency of light?

That question led to the quantum theory

When does an atoms emit a photon?

When its at a groudn state o a lower energy exited state it emits a photon of radiation

The energy of photon=hv is equal to

Te energy between the diffrence atoms initial state and final state

The fact that the hydrogens only give emited only a specific type of of frequencies meant!

That the frequencies diffrences between the atoms of hydrogens were fixed

Which meant

Hydrogen atoms exist at very specific states

In the nineteenth century what was discovered

The mathmatical relationships betweenn the wave lengths of the specific emissions of the hydrogens atom

When an e 2 falls back to e 1

E 2 - e 1 =2.718 ephoton = hv

The puzzle of the spectrum was solved din by?

1913 by a dsnish physicist niels bohr

He proposed a

hydrogen atom model thats linked the atoms electron to photon emission

According to the model

The electron can only cirlce the nucleus by some paths or some orbitals

The energy of those electrons are higher

That are farthur away from the atom

It can be compared to what?

A rung of a ladder your feet will allways be on a rung and your petentional energy proposes to the rung you are on for example first second and so on

While in the orbit the electrons

Sre not gaining or losing energy

Can it change orbits due to its energy ?

Yes it can

But when the electrons falls back to the lower energy

A photon is realeased and the procces is called emission

the photons energy is equal to?

The difference between the initial higher level and the newer lower level its going to

The gaining of energy to go to a higher level

Absorbtion

How ever what didnt this explain

It did not explain the spectra of atoms of more than one electron or the chemical behavior of atoms