Basic Compounds AI PDF

Evolution of atomic structure and periodic table (Basic concepts in Chemistry)  BASIC CONCEPTS OF CHEMISTRY Global context Statement inquiry Scientific and technical Scientists discern innovation patterns and use them o historical deve...

Evolution of atomic structure and periodic table (Basic concepts in Chemistry)  BASIC CONCEPTS OF CHEMISTRY Global context Statement inquiry Scientific and technical Scientists discern innovation patterns and use them o historical development of to construct systems atomic theory and discovery of different with rules and matter conventions that help o discovery of different to explain how the atomic models and world works. different matter o investigate properties of different states of matter Matter  Matter Can be separated physically Substance Mixture Homogeneous Heterogeneous Element Compound mixture mixture Can be separated chemically  Distinguishing Elements and Compounds Distinguishing Elements and Compounds An element is the simplest form of matter that has a unique set of properties. A compound is a substance that contains two or more elements chemically combined in a fixed proportion. Compounds can be broken down into simpler substances by chemical means, but elements cannot. Distinguishing Substances and Mixtures How can substances and mixtures be distinguished? If the composition of a material is fixed, the material is a substance. If the composition of a material may vary, the material is a mixture.  Symbols and Formulas Symbols and Formulas – What do chemists use to represent elements and compounds?  Symbols and Formulas Each element is represented by a one or two-letter chemical symbol.  Naming compounds 1. Compounds with oxygen Na2O-sodium oxide K2O-potassium oxide Fe2O3-iron (III)oxide CO2-carbon dioxide CO-carbon monoxide SO3-sulfur trioxide  Naming compounds 2. Acids HCl-hydrochloric acid H2SO4-sulfuroc acid H3PO4-phosphoric acid H2CO3-carbonic acid CH3COOH-acetatic acid (vinegar)  Naming compounds 3. Bases KOH-potassium hydroxide NaOH-sodium hydroxide Ca(OH)2-calcium hydroxide NH4OH-ammonium (hydroxide)  Naming compounds 4. Salts NaCl-sodium chloride KBr-potassium bromide CaCO3-calcium carbonate MgSO4-magnesium sulphate  Section Quiz – 1.Passing an electric current through a certain substance produces oxygen and sulphur. This substance cannot be a(n) compound. mixture. element. solution.  Section Quiz 2. Which of the following is a mixture? sodium chloride carbon dioxide sucrose air  Section Quiz. – 3.The symbol for the element potassium is K. Po. P. Pt.  Section Quiz. 4. What is the correct name of Al2O3 Aluminium oxide Aluminium trioxide Aluminium (III) oxide Dialuminium trioxide  BALANCING A CHEMICAL EQUATION Balance each of the following equations: 1. H2 (g)+ Br2 (l)→ HBr (l) 2. N2 (g) + H2 (g) → NH3 (g) 3. Sb (s) + O2 (g) → Sb4O6 (s) 4. Cu(NO3)2 (s) → CuO (s) + NO2 (g) + O2 (g) 5. (NH4)2Cr2O7 (s) → Cr2O3 (s) + N2 (g) + H2O (l) 6. C2H6 (g) + O2 (g) → CO2 (g) + H2O (l) 7. Al (s) + HgCl2 (aq) → AlCl3 (aq) + Hg (l) 8. FeS (s) + O2 (g) → Fe2O3 (s) + SO2 (g) 9. KOH (aq) + Cl2 (g) → KCl (aq) + KClO (aq) + H2O (l) 10. Ca(OH)2 (aq) + H3PO4 (aq) → Ca3(PO4)2 (aq) + H2O (l) 11. BaCl2 (aq) + Na2SO4 (aq) → BaSO4 (aq) + NaCl (aq) States of matter Solids Liquids Gasses  Solids Solids hold their own shape. Solids have weight. Solids take up space.  Liquids Liquids take the shape of their container. Liquids have weight. Liquids take up space.  Gasses Gasses spread out to fill the entire space given. Gasses have weight. Gasses take up space. Energy determines the state!  Particles in Solids: Are packed tightly together Have very little energy  Particles in Liquids: Are loosely packed Have medium energy levels  Particles in Gasses: Move freely Have LOTS of energy  Changing States There are several names for matter changing states: – State change – Phase change – Physical change  WHAT DO WE KNOW? There are three fundamental particles that together make up the atom. – Composed of electrons, protons, and neutrons The protons and the neutrons make up the center of the atom – Center of the atom is called the nucleus The protons & neutrons occupy  The electrons surround the nucleus and occupy most of the atom’s volume How, then, are atoms of hydrogen different from those of oxygen? – A subatomic particles from one type of atom looks like particles from other atoms CHEMICAL COMPOSITION OF ATOM # OF PROTONS + # OF NEUTRONS MASS Cl NUMBER 35 ATOMIC NUMBER 17 NUMBER OF PROTONS  IONS An element’s atoms are not always neutral in charge. When an atom loses or gains one or more of its electrons it becomes ion. An ion that has more electrons than protons has a negative electrical charge An ion that has fewer electrons than protons has a positive electrical charge Note: it’s the protons that define the type of atom it is, but the electrons define the atom’s charge.  For the following species determine no of protons, electrons and neutrons: – 11 23 Na – 20 40 Ca – 17 36 Cl- –8 16 O2- – 12 C4+  ISOTOPES Atoms with the same number of protons but contain different numbers of neutrons are called isotopes. Because isotopes of an element have different numbers of neutrons they have different mass numbers. Isotopes are chemically alike because they have identical numbers of protons and electrons – It’s the electrons and protons  EXAMPLE OF AN ISOTOPE ATOMIC MASS Cl 35 Cl 37 17 17 18 NEUTRON 20 NEUTRON S S ATOMIC NUMBER Chemical Periodicity The Periodic Law and the Periodic Table Group or Family (Vertical) Alkali Metals The Periodic table Noble Gases Alkaline Earths Halogens Main Group Transition Metals Main Group Lanthanides and Actinides The Periodic Law and the Periodic Table The Periodic Law and the Periodic Table Metals Good conductors of heat and electricity. Malleable and ductile. Moderate to high melting points. Nonmetals Nonconductors of heat and electricity. Brittle solids. Some are gases at room temperature The Periodic Law and the Periodic Table Atomic Number and Atomic Mass Trends in the Periodic Table Atomic Radius Atomic Radius – size of an atom Trends in the Periodic Table Electron Affinity Electron Affinity(Eea) - is a measure of the energy change when an electron is added to a neutral atom to form a negative ion. X(g) + e-  X-(g) Trends in the Periodic Table Size of Ions Trends in the Periodic Table Ionization Energy Ionization Energy (I or EI) - is the energy required to remove one mole of electrons from one mole of isolated gaseous atoms or ions X  X+ + e- Trends in the Periodic Table Electronegativity Electronegativity (En) - is a chemical property that describes the ability of an atom (or, more rarely, a functional group) to attract electrons (or electron density) towards itself in a covalent bond HI HBr HCl HF Melting points I.group:melting points decreases down the group( increasing atomic radius ) VII.group: melting point increases down the group ( increasing molar mass) Across the period: change in the pattern of melting point Trends in the Periodic Table Trends in the Periodic Table Chemical properties GROUPS Group I.; soft elements, vigorous reaction with water and air, reactivity increases down the group Reaction with water: Na(s) + H2O(l) → NaOH(aq) + H2 (g) Reaction with halogens: Na(s) + Cl2 (g) → NaCl (s) Chemical properties Group VII.; diatomic molecules, oxidizing agents ( fluorine is the strongest agent ), reactivity decreases down the group Oxidizing ability ( decreases down the group) Cl2 (aq) + 2 Br- (aq) → 2Cl- (aq) + Br2 (aq) F2> Cl2> Br2> I2 Chemical properties ELEMENTS OF THE SAME PERIOD ( PERIOD 3 ) 1. Conductivity; Metals: excellent conductors Metalloids; semiconductors Nonmetals; insulators 2. Reaction of oxides with water; Metallic oxides: ionic compounds, high melting and boiling points, conduct electricity when molten but not in solid state, form basic solutions Na2O (s) + H2O (l) → 2NaOH (aq) MgO (s) + H2O (l) → Mg(OH)2 (aq) Nonmetallic oxides: variable boiling and melting point ( SiO2 has very high boiling point-giant covalent structure), doesn't conduct electricity when molten, in reaction with water form acids P4O10 (s) + 6 H2O (l) → 4 H3PO4 (aq) SO3 (g) + H2O (l) → H2SO4 (aq) The Periodic Law and the Periodic Table Atomic Number and Atomic Mass