how to write a chemical equation and how to balance a chemical equation?
Answers
The reactant should be written on left hand side of the equation and products should be written on right hand side of the equation. A chemical equation should follow the law of conservation of mass, meaning all the atoms should be balanced.
Answer:
Identify each element found in the equation. The number of atoms of each type of atom must be the same on each side of the equation once it has been balanced.
What is the net charge on each side of the equation? The net charge must be the same on each side of the equation once it has been balanced.
If possible, start with an element found in one compound on each side of the equation. Change the coefficients (the numbers in front of the compound or molecule) so that the number of atoms of the element is the same on each side of the equation. Remember, to balance an equation, you change the coefficients, not the subscripts in the formulas.
Once you have balanced one element, do the same thing with another element. Proceed until all elements have been balanced. It's easiest to leave elements found in pure form for last.
Check your work to make certain the charge on both sides of the equation is also balanced.
Example of Balancing a Chemical Equation
? CH4 + ? O2 → ? CO2 + ? H2O
Identify the elements in the equation: C, H, O
Identify the net charge: no net charge, which makes this one easy!
H is found in CH4 and H2O, so it's a good starting element.
You have 4 H in CH4 yet only 2 H in H2O, so you need to double the coefficient of H2O to balance H.1 CH4 + ? O2 → ? CO2 + 2 H2O
Looking at carbon, you can see that CH4 and CO2 must have the same coefficient.1 CH4 + ? O2 → 1 CO2 + 2 H2O
Finally, determine the O coefficient. You can see you need to double the O2 coefficient in order to get 4 O seen on the product side of the reaction.1 CH4 + 2 O2 → 1 CO2 + 2 H2O
It's standard to drop a coefficient of 1, so the final balanced equation would be written:CH4 + 2 O2 → CO2 + 2 H2O