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In class today we started our new unit that has to do with Atom counting and balancing atomic equations. First is Atomic counting, it is something that we did in the begging of the year if you have an equation with 2c + 2H2 you draw two seperate C's and draw two H's together and have two of those. We also learned atomic counting, a couple examples of this are
1. 3 N2O + N2 N: 8 O: 3
2. 5 Ca(NO3)2 + 2 O2 Ca: 5 N: 10 O: 34
3. 5 C3H8O + 3 CO2 C:18 H:40 O: 11
The first number tells you how many molecules there are, the next number tells you how many of that type of atom are in that molecule. So you do the math from there.
The last thing we learned is balancing atomic equations. For example: 4 Li + 02-------2 Li20, you first find how much of each atom is in the both sides of the equation to see if there even, so in the equation above, there is 4 Li on the left side and 4 on the right, there is 2 O on the left and 2 O on the right, so this equation is right already you just have to show how you counted them. There are equations where you must show work: example: Al + Pb(NO3)2----- Al(NO3)3 + Pb, so your first step is to see how many Al are on each side, which they are equal.. so then you take the next atom which is Pb, that is equal.. so then you take the next atom which is NO3 and they are not the same, so you have to multiply the right side by 2 and the left by three, which makes it uneven again because the left side has 3Pb now so you have to multiply the left sides Pb by 3, and it is still uneven because the right side had 2 Al so you have to multiply the left sides Al by 2.. so your final equation is... 2Al + 3Pb(NO3)3----- 2Al(NO3)3 + 3Pb. And that is how you do balancing... you can do extra work on pg. 8 and 9

the next scriber will be..... Robert Maxwell Cohen.