Beryllium, magnesium, strontium, barium, or radium. Hope this helped :))
Yes, an example of a molecule would be CO2, which has no dipole moment but does have two polar bonds. Although CO2 has no dipole moment, its charge distribution gives rise to a quadrupole moment
Answer:
0.50 g Caffeine
Explanation:
Step 1: Given data
Concentration of caffeine by weight in tea leaves: 5.0%
Mass of tea leaves: 10. g
Step 2: Calculate the maximum weight of caffeine that can be isolated
The concentration of caffeine by weight in tea leaves is 5.0%, that is, there are 5.0 g of caffeine per 100 g of tea leaves. The maximum weight of caffeine in 10. g of tea leaves is:
10. g Tea leaves × 5.0 g Caffeine/100 g Tea leaves = 0.50 g Caffeine
Answer:
0.172 M
Explanation:
The reaction for the first titration is:
First we <u>calculate how many HCl moles reacted</u>, using the <em>given concentration and volume</em>:
- 19.6 mL * 0.189 M = 3.704 mmol HCl
As one HCl mol reacts with one NaOH mol, <em>there are 3.704 NaOH mmoles in 25.0 mL of solution</em>. With that in mind we <u>determine the NaOH solution concentration</u>:
- 3.704 mmol / 25.0 mL = 0.148 M
As for the second titration:
- H₃PO₄ + 3NaOH → Na₃PO₄ + 3H₂O
We <u>determine how many NaOH moles reacted</u>:
- 34.9 mL * 0.148 M = 5.165 mmol NaOH
Then we <u>convert NaOH moles into H₃PO₄ moles</u>, using the <em>stoichiometric coefficients</em>:
- 5.165 mmol NaOH *
= 1.722 mmol H₃PO₄
Finally we <u>determine the H₃PO₄ solution concentration</u>:
- 1.722 mmol / 10.0 mL = 0.172 M