Writing Chemical Equations Writing Equations Types of Equations Lab Potpourri $200 $200 $200 $200 $200 $400 $400 $400 $400 $400 $400 $600 $600 $600 $600 $600 $600 $800 $800 $800 $800 $800 $800 $1000 $1000 $1000 $1000 $1000 $1000 Balancing Equations Just Memorize $200 Final Jeopardy Final Jeopardy Combustion Final Jeopardy 2C4H10 + 13 O2 -----> 8CO2 + 10 H2O Write the complete balanced equation for the combustion of C4H10. $200 The number you put in front of a compound to balance an equation. A coefficient $400 To balance a compound so charges = zero and it equals the numbers of atoms in a compound Purpose of a subscript $600 False True or False: The coefficients on one side of the arrow will equal the coefficients on the other side. $800 When you have an odd number of oxygens on the right side and an even on the left side of the arrow. Under what circumstances is it easier to balance an equation by making a ratio in front of the Oxygen atom $1000 _MgO2 should be MgO Why won’t this equation balance: _MgCO3(s) --->_MgO2 (s)+_CO2(g) $200 CH4 Formula for Methane $400 Increases due to the adding of more energy levels Trend of atomic size going down a family… $600 Trend of atomic size going across a period What Decreases due to energy level staying the same, while effective nuclear charge increases (more pull on valence electrons)? $800 Ionization Energy What is the energy needed to move an electron? $1000 The effective nuclear charge and atom size What are factors which affect ionization energy and how they affect it ? $200 Trend of ionization energy going down a family What decreases (easier to remove) because size is bigger, so valence electrons are further away ? $400 Trend of ionization energy going across a period What increases (harder to remove) due to effective nuclear charge increasing (more pull - more likely to attract electrons) ? $600 Electronegativity What energy is needed to add an electron (likeliness to gain)? $800 effective nuclear charge and atom size What factors which affect electronegativity and how they affect it ? $1000 Decreases.. if size is bigger, less pull from nucleus •What is the trend of electronegativity going down a family $200 Combustion What type of reaction is usually inventoried for balancing with CHO $400 Ionic Size Size of an ion $600 to organize elements in meaningful way Why was periodic table developed? $800 Mendeleev - increasing molar mass, while today’s is increasing atomic number How was Medeleevs scheme for listing elements different from that used in the modern periodic table? $1000 elements in same group have same number of valence electrons What relationship can be seen between an elements placement within a group and its electron configuration? $200 Noble gases had not been discovered yet due to their inactivity Why did Group 8 not appear on the Mendeleev periodic table? $400 increasing tendency to form neg ions therefore use less energy (minus -: Exothermic Trend of electron affinity across left to right $600 farther from nucleus therefore uses less energy to add an electron also shielding can add electrons Trend of electron affinity down top to bottom $800 X + e− → X− Equation electron affinity $1000 M(g) + hn ® M+ + e-. Equation for ionization energy $200 both negative ions (right side) give off energy to gain an electron + ions use energy Electron affinity energy can be what: + or -? $400 1) shielding 2) Effective (Strong) nuclear charge 3) add another orbit of electrons increases distance from nucleus Name 3 concepts that can affect periodicity $600 Protons and neutrons in element 114 What exactly do these two pictures represent and where are the from? $800 Dalton, Thompson, Rutherford and Bohr…Schrödinger, and Heisenberg, st 1 Name the five scientists in “The Atom Song” $1000 1s2 2s2 2p6 3s2 3p2 and [Ne] 3s2 3p2 Long and short electron configuration for silicon. Daily Double You could not replace any other metal When we talked about the “REACTIVITY SERIES” If you were a metal at the bottom of the list, what would this mean? The Jeopardy champion!