Johann Kelly T. AlmelorBSHRM – 1B

TYPES OF SERVICE

What is food service?There are some basic principles in food and beverage service that a waiter must know:

• When food is served by the waiter at the table from a platter onto a guest plate, the service is done from the left.• When food is pre-plated the service to the guest is usually done from the right, though modern convention permits service from the left also.• All beverages are served from the right.• Soups are served from the right unless it is poured by a waiter from a large tureen into a soup cup in which case it is done from the left of the guest.• Ladies are always served first and the remaining guests clockwise. Soiled plates should always be cleared from the table from the right.• Empty crockery and fresh cutlery are always served from the right. Never reach across a Customer. Hence, when a guest is present at the table, all items and equipment on the right of guest must be placed from the right and that on the left from the left.

HISTORY OF THE ATOM

460 BC Democritus develops the idea of atoms

he pounded up materials in his pestle

and mortar until he had reduced

them to smaller and smaller particles

which he calledATOMA

(greek for indivisible)

HISTORY OF THE ATOM

1808 John Dalton

suggested that all matter was made

up of tiny spheres that were able to

bounce around with perfect elasticity

and called themATOMS

HISTORY OF THE ATOM

1898 Joseph John Thompson

found that atoms could sometimes

eject a far smaller negative particle

which he called an

ELECTRON

HISTORY OF THE ATOM

Thompson develops the idea

that an atom was made up of

electrons scattered unevenly

within an elastic sphere

surrounded by a soup of

positive charge to balance the

electron's charge

1904

like plums surrounded by pudding.

PLUM PUDDING

MODEL

HISTORY OF THE ATOM

1910 Ernest Rutherford

oversaw Geiger and Marsden carrying

out his famous experiment.

they fired Helium nuclei at a piece of

gold foil which was only a few atoms

thick.

they found that although most of

them passed through. About 1 in

10,000 hit

HISTORY OF THE ATOM

gold foil

helium nuclei

They found that

while most of the

helium nuclei

passed through the

foil, a small number

were deflected and,

to their surprise,

some helium nuclei

bounced straight

back.

helium nuclei

HISTORY OF THE ATOM

Rutherford’s new evidence allowed him to propose

a more detailed model with a central nucleus.

He suggested that the positive charge was all in a

central nucleus. With this holding the electrons in

place by electrical attraction

However, this was not the end of the story.

HISTORY OF THE ATOM

1913 Niels Bohr

studied under Rutherford at the

Victoria University in Manchester.

Bohr refined Rutherford's idea by

adding that the electrons were in

orbits. Rather like planets orbiting

the sun. With each orbit only able

to contain a set number of

electrons.

Atomic Structure

Atoms are composed of 2 regions:

Nucleus: the center of the atom that contains the mass of the atom

Electron cloud: region that surrounds the nucleus that contains most of the space in the atom Nucleus

Electron

Cloud

Atomic Structure

Atomic Structure

Atomic Structure

What’s in the Nucleus?

The nucleus contains 2 of the 3 subatomic particles:

Protons: positively charged subatomic particles

Neutrons: neutrally charged subatomic particles

What’s in the Electron Cloud?

The 3rd subatomic particle resides outside of the nucleus in the electron cloud

Electron: the subatomic particle with a negative charge and relatively no mass

Electron Cloud Model

How do the subatomic particles balance each other?

In an atom:The protons = the electrons

If 20 protons are present in an atom then 20 electrons are there to balance the overall charge of the atom—atoms are neutral

The neutrons have no charge; therefore they do not have to equal the number of protons or electrons

How do we know the number of subatomic particles in an atom?

Atomic number: this number indicates the number of protons in an atom

Ex: Hydrogen’s atomic number is 1So hydrogen has 1 proton

Ex: Carbon’s atomic number is 6So carbon has 6 protons

**The number of protons identifies the atom. Ex. 2 protons = He, 29 protons = Cu

How do we know the number of subatomic particles in an atom?

Mass number: the number of protons and neutrons in the nucleus

Ex: hydrogen can have a mass of 3.

Since it has 1 proton it must have 2 neutrons

# of neutrons = mass # - atomic #

Determining the number of protons and neutrons

Li has a mass number of 7 and an atomic number of 3

Protons = 3 (same as atomic #)Neutrons= 7-3 = 4 (mass # - atomic #)

Ne has a mass number of 20 and an atomic number of 10

Protons = 10Neutrons = 20 - 10= 10

What about the electrons?

The electrons are equal to the number of protons

So e- = p = atomic #Ex: He has a mass # of 4 and an atomic # of 2

p+ = 2no = 2e- = 2

Determine the number of subatomic particles in the following:

Cl has a mass # of 35 and an atomic # of 17p+ = 17, no = 18, e- = 17

K has a mass # of 39 and an atomic # of 19P+ = 19, no = 20 e- = 19

How exactly are the particles arranged?

Bohr Model of the atom:Reviewers think this could lead to misconceptions!

All of the protons and the neutrons

The 1st ring can hold up to 2 e-

The 2nd ring can hold up to 8 e-

The 3rd ring can hold up to 18 e-

The 4th ring and any after can hold up to 32 e-

What does carbon look like?

Mass # = 12 atomic # = 6

p+ = 6 no = 6 e- = 6

6 p and 6 n live in the nucleus