Dalton s Atomic Theory

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Dalton's Atomic Theory 1. Components are made of modest particles called molecules . 2. All iotas of a given component are indistinguishable (not precisely; isotopes) 3. The iotas of a given component are unique in relation to those of some other component. 4. Particles of one component can join with molecules of different components to shape mixes. A given compound dependably has a similar relative numbers and sorts of iotas. 5. Particles are resolute in substance forms. That is, molecules are not made or decimated in concoction responses. A compound response essentially changes the way the molecules are assembled together.

Laws of Chemical Combination Law of Definite Proportions : Different specimens of a similar compound dependably contain its constituent components in similar extents by mass This is likewise called the Law of Constant Composition Suppose we investigate tests of water from various sources We will discover in each example a similar proportion by mass of hydrogen to oxygen.

So… A 10.0 gram test of water, H 2 O, is contained 8.9 grams oxygen and 1.1 grams hydrogen. Therefore, a 100.0 gram test of water, is contained 89.0 grams of oxygen and 11.0 grams of hydrogen.

Laws of Chemical Combination Law of Multiple Proportions (or, Dalton's Law) : If two components can consolidate to shape more than one compound, then the masses of one component that join with a settled mass of the other component are in the proportions of little entire numbers For example, the particle carbon frames two stable mixes with the molecule oxygen: Carbon Monoxide (C 1 O 1 ) and Carbon Dioxide (C 1 O 2 ) Neither C 1.2 O 1.3 nor C 1.2 O 2.2 , separately

Formulas of Compounds Chemical Formula : An expression demonstrating the synthetic structure of a compound regarding the images for the iotas of the components included. Rules for Writing Formulas 1. Every molecule present is spoken to by its component image. 2. Metals are composed initially, trailed by non-metals. 3. The quantity of each sort of iota is demonstrated by a subscript kept in touch with the privilege of the component image. 4. At the point when just a single iota of a given sort is available, the subscript 1 is not composed.

Formulas of Compounds Write the equation for each of the accompanying aggravates: (an) A particle contains four phosphorous iotas and ten oxygen molecules. (b) A compound contains one uranium molecule and six fluorine particles. (c) A compound contains one aluminum particle and three chlorine molecules.

The Structure of the Atom : The fundamental unit of a component that can go into synthetic blend They are made of considerably littler particles called subatomic particles (Dalton wasn't right!) Electrons Protons Neutrons

Summary of the Structure of the Atom Mass and Charge of Subatomic Particles Particle Mass (grams) Charge Unit Electron 9.1095 x 10 - 28 - 1 Proton 1.67252 x 10 - 24 +1 Neutron 1.67495 x 10 - 24 0 Nucleus in focal point of molecule – houses protons & neutrons Electrons around core in orbitals

Atomic Symbols Atomic Number : The quantity of protons in the core of an iota. Mass Number : The aggregate number of neutrons (variable) and protons exhibit in the core of an iota.

Atomic Symbols We utilize the image to speak to the particle X = the image of the component A = the mass number Z = the nuclear number How would we compute the quantity of neutrons? Mass Number = Protons + Neutrons Thus, neutrons = A - Z

Atomic Symbols: Practice Give the nuclear image for an animal categories that houses 38 protons and 48 neutrons. Give the nuclear image for an animal groups that houses 38 protons and 50 neutrons. What is the distinction?

Isotopes Atoms having the same nuclear number yet unique mass numbers; i.e., diverse number of neutrons. The Periodic Table houses normal mass numbers in light of percent plenitude of every isotope.

Isotopic wealth % plenitude = (# iotas of isotope/aggregate # of particles of all isotopes) x 100% For ex: component X has two isotopes X-20 and X-21 Out of each 100 molecules of X, 90 are X-20 and the rest (10) are X-21 So, X-20 has a plenitude of (90/100) x 100% = 90% And X-21 has a plenitude of 10%

Atomic weight Atomic weight = (% wealth isotope/100) (mass of isotope 1) + … A normal estimation Shown on the occasional table Measured in nuclear mass units (amu) But more regularly in molar mass or grams/mole Will examine anon

Practice: What's the nuclear weight? B-10 = 19.91% wealth 10.0129 amu = mass B-11 = 80.09% plenitude 11.0093 amu = mass

Atomic mass unit Amu or u = 1/12 th mass of C-12 = 1.661 x 10 - 24 g (C-12= 12 amu) Used for subatomic particles

The Mole = amt that contains the same number of "things" as there are iotas of 12 g of C-12 1 mole = 6.022 x 10 23 particles Molar mass (MM) = mass in grams per 1 mole of particles (g/mol)

Practice How much does one molecule of argon (Ar) weigh?

Practice what number moles and molecules of Ar are in a 5.00 gram test?

Your turn what number grams of niobium (Nb) are there in a 2.00 mole test? What number of iotas?

Introduction to the Periodic Table

What do the numbers mean? Every cell houses: Elemental image Elemental name Atomic number Molar mass Sundry data Let's investigate

Introduction to the Periodic Table Elements symbolized by it is possible that one capital letter or two letters; first capital, second lower-case Examples: B = boron Cl = chlorine P = phosphorus Na = Sodium Symbols don't generally coordinate with English names Because utilize Greek and Latin words

Introduction to the Periodic Table Groups : The components in a vertical segment of the occasional table "Old" School: Group-An and Group-B Taller gatherings: A Shorter gatherings: B "New" School: Groups I - XVIII Elements characterized in gatherings in view of valence electron design: comparable synthetic properties Group names: Alkali Metals : The Group 1A components (Li  Fr) Alkaline Earth Metals : The Group 2A components (Be  Ra) Halogens: The Group 7A components (F  At) Noble Gasses : The Group 8A (He  Rn) Transition Metals : The Group-B components

Introduction to the Periodic Table Period : The components in every flat line of the intermittent table There are 7 periods Increase in nuclear number setting off to the correct Two columns at base are: Lanthanides or uncommon earth metals Actinides (contain transuranium metals)

Introduction to the Periodic Table Elements can be separated into 3 classifications: Metals Metalloids Nonmetals Step-stepping stool isolates metals from nonmetals Metalloids encompass step-stepping stool Periodic Table about 75% metals Let's mark the Periodic Table freebee!

Introduction to the Periodic Table: Metals 1. Effective conduction of warmth and power 2. Flexibility (they can be pounded into thin sheets) 3. Flexibility (they can be maneuvered into wires) 4. A glossy (sparkly) appearance

Introduction to the Periodic Table: Metalloids Or semimetals, have properties that fall between those of metals and nonmetals

Introduction to the Periodic Table: Nonmetals Usually poor transmitters of warmth and power More fluctuated physical properties than metals

Natural States of the Elements All metals and metalloids are strong Except mercury = mercury Non-metals both strong and vaporous Noble gasses H, O, N, F, Cl Some nonmetals are diatomic A particle that comprises of two comparative iotas All incandescent light Oxygen, nitrogen, and hydrogen One is fluid Bromine

Natural States of the Elements Allotropes : at least two types of a similar component that vary fundamentally in compound and physical properties. Case Phosphorus: red and white Carbon: Diamond, Graphite, Buckyball