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Calculating number of moles by the T chart method
Determination of number of moles by the T-chart method
How many moles in 25 g of Fe ?
1. Make a T chart
2. Put the information that is given to you along with the units on the left most corner of the T
3. Therefore 25 g will be placed in the leftmost upper corner.
4. Now in the box diagonally opposite to it, write the units g.
5. In the right hand upper corner you write the desired unit which is mole.
6. This would be 1 mole
7. In the right hand bottom box you write the value of 1 mole in g which is your conversion factor
8. 1 mole of Fe= 56 g
9. Proceed with the math, cancel out common units.
25g X 1 mole / 56g = 0.446 moles of Fe
Similarly, you can calculate the number of moles of -
15 g of O2 as 0.468 moles
15 g in the left most top corner
1 mole of O2 is 32 g. Write 32 g in the right most bottom corner of the T chart
write 1 mole in the topmost right corner of the T
Cancel common units and proceed with the math to give number of moles of O2.