NEED CHEMISTRY HELP!!! (balancing chemical equations)?

1) Na + H^2O --> NaOH

answer:

2Na + 2H2O -->2NaOH +H2

----------------------------------------------------

2) CO^2 + H^2O --> C^6H^12O^6 + O^2

answer: reaction won't go the way wrote...have to reverse it:

C6H12O6 + 6O2 ---> 6CO2 + 6H2O

unless this is photosynthesis....if there is energy present and chlorophyll then a plant can convert CO2 and water into sugar and oxygen..so I'm wrong, just reverse the order above and the reaction is fine in that direction

------------------------------------------------------

3) HCl + CaCO^3 --> CaCl^2 + H^2O + CO^2

answer: CaCO3 + 2HCl ---> CaCl2 + CO2 +H2O

Just start by looking at the most complex compound and/or compound with the least common elements and adjust the necessary co-efficients on either side so that the number of elements are equal on each side of the equation. Just work in steps and keep making sure the number of elements will be equal on both sides. It's usually best to do oxygen last and hydrogen next to last.

The first one appears to be missing H^2 (gas) on the right side of the equation so it should be balanced as 2Na + 2H^2O--> 2NaOH + H^2 or Na + H^2O--> NaOH + 1/2H^2

For the second one just start with the large compound on the right and balance the carbon # on the left side by putting a 6 in front of the CO^2 then notice the # of hydrogens in the large compound (12) so to balance the left side you must put a 6 in front of the H^2O to get 12 (6x2=12). Like I said earlier this is why you leave oxygen till last, you now have more oxygen on the left-side, so count them up (18). You can see that the large compound on the left has 6, so 12 more must be on the right side, so adjust the O^2's co-efficient accordingly by placing a 6 in front of it. The final balanced equation should look like this: 6CO^2 + 6H^2O --> C^6H^12O^6 + 6O^2

For the last one just use the same approach as before, start by looking at Cl, Ca, or C. In this case their is an imbalance of Cl (2 Cl on the right and only one on the left) so begin there by adjusting the left side's Cl compound. This third one should look like 2HCl + CaCO^3 --> CaCl^2 + H^2O + CO^2 Notice that when we added the 2 to the HCl we not only added an extra Cl, but an extra H, which we needed to balance the H on the other side. This was a somewhat simpler equation to balance than quesiton 2

1. impossible

2. 6CO^2 + 6H^2O --> C^6H^12O^6 + 6O^2

3. 2HCl + CaCO^3 --> CaCl^2 + H^2O + CO^2

1 - it seems like you are missing a term... I think the equation should be 2Na + 2H2O --> 2NaOH + H2

2 - 6CO2 + 6H2O --> C6H12O6 + 6O2

3 - 2HCl + CaCO3 --> CaCl2 + H2O + CO2

1) 2Na + 2H2O ---> 2NaOH + H2

2) 6CO2 + 6H2O ---> C6H12O6 + 6O2.

3) CaCO3 + 2HCl ---> CaCl2 + CO2 +H2O