The mole fraction of ethanol is 0.6. A 10 mL volumetric pipette must be used for to measure the 10 mL of ethanol. The vessel should be clean and purged.

Explanation:

For calculating mole fraction of ethanol, the amount of moles ethanol must be calculated. Using ethanol density (0.778 g/mL), 10 mL of ethanol equals to 7.89 g of ethanol and in turn 0.17 moles of ethanol. The same way for calculate the amount of water moles (ethanol density=0.997 g/mL). 2 mL of water correspond to 0.11. The total moles are: 0.17+0.11=0.28. Mole fraction alcohol is: 0.17/0.28=0.6

5 0

3 years ago

Calculate the formal charges of the atoms in co co2 and co32-

Dimas [21]

Every element in the compound has its own formal charge. The formula is:
Formal charge = Valence electrons - Nonbonding electrons - Bonding electrons/2
Let the Lewis structure of the compound aid you.

1. For CO:
Formal charge of C = 4 - 2 - 6/2 = -1
Formal charge of O = 6 - 2 - 6/2 = +1

2. For CO₂:
Formal charge of C = 4 - 0 - 8/2 = 0
Formal charge of each O = 6 - 4 - 4/2 = 0

3. For CO₃²⁻:
Formal charge of C: 4 - 0 - 8/2 = 0
Formal charge of two O's single-bonded to C = 6 - 6 - 2/2 = -1
Formal charge of the O double-bonded to C = 6 - 4 - 4/2 = 0

6 0

4 years ago