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Heat VS Temperature Heat = Thermal energy Thermal Energy = The total energy of all the particles in a material Temperature = A measure of the average energy of the particles in a material. Quiz with Thermal energy Both cups have coffee that is at a temperature of 80 degrees Celsius. Which has more heat energy? If you answered the bigger cup, you are correct because it contains a higher amount of thermal energy than the smaller cup.  Ways of measuring temperature There are 3 popular scales for measuring temperature - Celsius, Fahrenheit, and Kelvin Out of these 3, Celsius is the most common measuring scale Freezing point of water is at 0 Degrees Celsius Boiling point of water is at 100 Degrees Celsius (at sea level) Kelvin Scientists use Kelvin to measure the behavior of Gases To convert Celsius to Kelvin -  Add 273 to Celsius.  For example Freezing point of water is 273 Kelvin Boiling point of water is 373 Kelvin "Absolute Zero" is the coldest possible temperature, and is mea

Kinetic Theory of Matter is basically the theory of Moving Particles. Particles are always moving, they will collide with each other with sufficient energy - that's when chemical bond which is broken {reactant side}. This energy is called [Activation Energy - symbol "Ea"] REMEMBER: Energy of the reaction < Ea -----> The reaction will not proceed. Energy of the reaction > Ea -------> Reaction will proceed. Particle Theory of Matter: All matter is made of extremely tiny particles. All pure substances are made of their own kind of particles. All particles are moving. Particles at highest temperature move faster than those of lower temperature. Particles are attracted to each other.

  Energy Changes in a Chemical Reaction Exothermic                                                                                                Endothermic                            Energy will be given out/Release                                                              Energy if taken in/input of energy Rise in temperature ----> heat is                                                               Fall in temperature ----> heat is given out to surroundings                                                                          taken in from the surroundings Delta H is negative                                                                                   Delta H is positive Ex: Respiration:                                                                                             Photosynthesis: C6 H12 06 =02 ------> CO2 + H2O                                                      CO2 + H2O ------> C6 H12 O6 + O2 Energy Level Diagrams:

Heating curve                                                                             This is a heating curve. In the heating curve, we can see an increase in the amount of kinetic energy stored within the particle as time passes, and also a change in the state of matter, from solid to liquid to gaseous. The diagonal line represents an increase in temperature, and the horizontal line represents a change in the state of matter. The temperature doesn't increase during the time when the state of matter is changing because the heat is used to create more intermolecular space and is released, therefore keeping the temperature of the object the same. Cooling curve This is a cooling curve. In the cooling curve, we can see a decrease in the amount of kinetic energy stored within the particle as time passes, and also a change in the state of matter, from gaseous to liquid to solid. The diagonal (slightly curved) line represents a decrease in temperature, and the horizontal line represen

Learning Objective: Mendeleev and Monsey's Periodic Table Development of the Periodic Table Need for Periodic Classification of Elements: Easier to classify and study the known elements. Organize the known information about elements. Patterns and trends in the behavior could be correlated. Lavoisier(Father of Modern Chemistry) divided elements into two main types known as metals and non metals. Dobereiner's Triad : In 1817, Johann Wolfgang Dobereiner's, classified elements into groups based on their properties. Basis of arrangement atomic mass. Atomic mass is the sum of the number of protons and neutrons in an element. Law of Triads: Dobereiner's Law of Triads sates that when three element in a triad are listed in the increasing order of their atomic masses, the atomic mass of the middle element will roughly be the average of the atomic masses of the other two elements. Limitations of  Triad: All known elements could not be classified into groups of triads on the basis

  Learning Objective: Collecting Information/understand the Periodic Table Activity: Group number to Valency Activity: To understand the relation between valency and group number of elements in the Periodic Table Write the electronic distribution of element (1 to 20) following the octet rule. Circle the valence electrons for the elements - Each with a different color Now group the elements with same valence electrons in a group and arrange them in ascending order. Check the periodic table if it follows the same pattern Octet Rule:     1.  Maximum possible electrons in the first shell is 2. (2n^2 where n is the shell number)     2.  The outermost or the last shell cannot have more than 8 electrons My Answer: Hydrogen (H) - 1;  1 Helium (He) - 2;  2 Lithium (Li) - 3;  2,1 Beryllium (Be) - 4;  2,2 Boron (B) - 5;  2,3 Carbon (C) - 6;  2,4 Nitrogen (N) - 7;  2,5 Oxygen (O) - 8;  2,6 Fluorine (F) - 9;  2,7 Neon (N) - 10;  2,8 Sodium (Na) - 11;  2,8,1 Magnesium (Mg) - 12;  2,8,2 Aluminum (Al)