False. Bonds between nonmetals are covalent.
Answer:
6.04 g O2
Explanation:
6.80 g H2O x (1 mol/18.0 g) x (1 O2/2 H2O) x (32.0 g/1 mol) = 6.04 mol O2
Answer:
The move from Level n=3 to Level n=2 has the long wavelength.
Explanation:
First, due to the selection rules, only transitions between adjacent levels are allowed, thus, only a transition between Level n=3 to Level n=2 or Level n=5 to Level n=4 are allowed. The two first options are wrong.
Second, analyzing the transition between Level n=3 to Level n=2 and the transition between Level n=5 to Level n=4 it is necessary to think in terms of the equation of the difference of energy for these type of transitions:
Δ (1)
The difference in energy (ΔE) is directly proportional to the quadratic difference between the 'n' levels of transition. Therefore, If the transition occurs between smaller 'n' levels the difference of energy will be smaller too.
Also, the energy (ΔE) is inversely proportional to the wavelength (λ) so a smaller energy means a larger wavelength.
ΔE = c / λ (2)
Hence, the move from Level n=3 to Level n=2 has a long wavelength.
In order to calculate this wavelength is necessary to replace the data on equation (1) and (2).
<span>The mixture of pepper and water is a suspension because of the particles, You see, a suspension is a mixture in which particles can see and easily separated by setting or filtration. Unlike a solution, a suspension does not have the same properties throughout it contains visible particles that are larger than the particles in solutions or colloids </span>
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