The following chemical equation shows the incomplete formula for burning methanol. The question mark represents the unknown number of oxygen (O2) molecules. How many molecules of O2 are needed to balance this chemical equation?
2CH₃OH + ?O₂ > 2CO₂ + 4H₂O
A. 1
B. 3
C. 5
D. 6
Please Help!!
Count it up. Don't make a hard problem out of it.
Look on the right. How many O atoms do you see? I see 4 from 2CO2 and 4 from 4H2O or 8 total. You have on the left 2 from the 2CH3OH so you need 6 more. How can you get that? You must have ? of O2.
Thank you
but which one is it
Is it six
To balance a chemical equation, you need to ensure that the same number of atoms of each element is present on both sides of the equation. In this case, we need to balance the number of oxygen (O) atoms.
Let's start by counting the number of oxygen atoms on each side of the equation:
On the left side:
2 CH₃OH + ?O₂
On the right side:
2 CO₂ + 4 H₂O
From the equation, we can see that there are 4 oxygen atoms on the right side of the equation (2 CO₂), but we don't know how many oxygen (O) molecules are needed on the left side.
To determine the number of molecules of O₂ needed, we need to balance the oxygen atoms. We can do this by comparing the number of oxygen atoms on each side of the equation.
On the left side, we have 2 oxygen atoms from the 2 CH₃OH molecules. On the right side, we have 4 oxygen atoms from the 2 CO₂ molecules. Therefore, we need an additional 2 oxygen atoms on the left side to balance the equation.
Since each O₂ molecule contains two oxygen atoms, we need 2/2 = 1 molecule of O₂.
Therefore, the correct answer is A. 1 molecule of O₂ is needed to balance the chemical equation.
Remember, balancing chemical equations is a crucial skill in chemistry. It involves manipulating the coefficients in the equation to ensure that the number of atoms of each element is the same on both sides. This helps to maintain the law of conservation of mass.