PPT-Chemical Equations Laws The Law of Conservation of Mass

In a chemical reaction the total mass of everything at the end of the reaction is the same as the total mass at the beginning The Law of Constant Composition However you make a compound it always contains the same elements in the same proportions by mass. HIGHER LESSON. Learning Objectives. To . explain. what chemical equations tell us about chemical reactions. To . explain. how we use equations to calculate masses of reactants and products. HIGHER LESSON. Law of Conservation of Mass. The law of conservation of mass states that in any given chemical reaction, the total mass of the reactants equals the total mass of the products.. Chemical equations obey the law of conservation of mass. They show that all the atoms in the reactants are still present in the products.. Re-Made Version. Coupled Motion. Coupled motion problems are problems in which the movement of one object directly impacts the motion of another object.. We have already briefly covered this topic when talking about pulleys.. What happens in a Chemical Reaction?. Chemical . bonds. in the reactants are . broken. , then atoms are . rearranged. to form new substances (. products. ). . The amount of . matter. does not . change. They tell us how much of each substance is involved in a chemical reaction. 2H. 2. + O. 2. .  2H. 2. O. 2 moles of hydrogen react with 1 mole of oxygen to make 2 moles of water. This is useful because now we can use it to work out what mass of hydrogen and oxygen we need and how much water is made. NOTES. MOLECULE. A . molecule. is . two . or more atoms that have chemically . combined.. Examples. : . H. 2. O. & O. 2. CHEMICAL FORMULA. A . Chemical Formula . is a description of the number and kind of atoms found in a single molecule of a substance, using the . What happens in a Chemical Reaction?. Chemical . bonds. in the reactants are . broken. , then atoms are . rearranged. to form new substances (. products. ). . The amount of . matter. does not . change. Chemical Changes vs. Physical Changes. Physical changes are . changes in the physical appearance, state or size of a substance. .. Chemical changes are . changes in the arrangements and connections between ions and atoms, and a change in chemical properties.. In a chemical reaction the total mass of everything at the end of the reaction is the same as the total mass at the beginning.. The Law of Constant Composition. However you make a compound, it always contains the same elements in the same proportions by mass.. Ionic compounds can form from transition metals. Transition metals do not always follow the patterns that we discussed. Can have more than one oxidation number (charge. ). To identify the charges of transition metals, roman numerals are placed in their name, directly after the transition metal. . 1. Describing a Chemical Reaction. A chemical reaction = the process by which one or more substances is changed into one or more different substance. s.. Reactants. = the original . substance(s. 10.1 . Reactions and . Equations. Evidence of Chemical Reactions. ..  . The process of which the atoms of one or more substances are rearranged to form different substances is called a . Chemical Reaction. Chemistry 1-2. Mr. . Chumbley. Section 1: Describing Chemical Reactions. Chemical Reactions. A . chemical reaction . is a process by which one or more substances change to produce one or more different substances. Give an example of a non-communicable disease.. What is a pathogen?. Name the four types of pathogens.. Which pathogen is the usual cause of food poisoning?. Name another disease this type of pathogen can cause in humans..