Chemical+Equations+and+the+Conservation+Laws

=VI.1 Chemical Equation =

__Purpose__: to understand what is chemical reaction equation and remember details in the equations.
====As we know, chemical reaction means there are new substances be produced. But when chamical reations occur, it aslo follow by physical reactions. For instance, colours of materials, the temperature and new states may be formed. ==== ====CHEMICAL REACTION EQUATION: an equation that shoes the chemicals used up and produced during a chemical reaction. ====

COEFFICIENTS: numbers in front of the symbols
====The meaning of "→ ": reacatants exits, then as time passes products exist. (We also use words to show reactants and products, that is called CHEMICAL WORD EQUATION.) ====

=VI.2. The Conservation Laws = __Purpose:__ --understand the meaning of system (closed and open system) --understand what is conservation laws and know how to identify each of them

PART1
Vocabulary:--SYSTEM: the part of the universe being studied in a particular stituation. Examples: A beaker full of water is an example of OPEN system when the water is considered to be the "system". Because the heat can get into the beaker and water, so that makes the water vapoured to the air.But if the beaker is seal which nothing can get in or out of the tube, so that is the CLOSED system.
 * Closed system: things cannot get into/out of it
 * Open system: things can get into/out of it

PART2
Vocabulary-- CONSERVED: the quantity doesn't change when a reaction happened--the system is closed -- CONSERCATION LAW: EXERCISES: 1. Identify which consercation laws are being broken in the following situations? (It is not necessarily be broken） a). 3H2O+O2→3H2O b). NaOH+H2SO4→Al2(SO4)3+H2O c). At STP, 10.0g of chlorine gas and 28.0g of oxygen gas produce 38.0g of chlorine dioxide gas. d). Fe3+ + S2- →FeS
 * < Naming of the law of conservaion ||< Thing does not change in a closed system during a chemcal reaction ||
 * < The law of conservation of MASS ||< Total Mass ||
 * < The law of conversation of ATOMS ||< Total number and type of atoms ||
 * < The law of consercation of ELECTRICAL CHARGE ||< Total electrical charge ||
 * The law of conservation of ENERGE || total amount of energe ||

2. Which of the following are conserved in a chemical reaction? a) temperature b). phase c). total mass d). moles

Answers: 1.a). The law of conservation of ATOMS b). The law of conservation of ATOMS c). The law of conservaton of MASS d). The law of conservation of ELECTRICAL CHARGE

2 (c)