Answer is: the osmotic pressure of aqueous solution of aspirin is 0.0407 atm.
m(C₉H₈O₄) = 75 mg ÷ 1000 mg/g = 0.075 g.
n(C₉H₈O₄) = 0.075 g ÷ 180.16 g/mol.
n(C₉H₈O₄) = 0.000416 mol.
c(C₉H₈O₄) = 0.000416 mol ÷ 0.250 L.
c(C₉H₈O₄) = 0.00167 M; concentration of solution.
T(C₉H₈O₄) = 25°C = 298.15 K; temperature in Kelvins.
R = 0.08206 L•atm/mol•K; universal gas constant.
π = c(C₉H₈O₄) • T(C₉H₈O₄) • R.
π = 0.00167 mol/L • 298.15 K • 0.08206 L•atm/mol•K.
π = 0.0407 atm.
Explanation:
The sum of total number of protons present in an element is known as atomic number of the element.
- As atomic number of Cs is 55.
And, it is known that for a neutral atom the number of protons equal to the number of electrons.
Since, no charge in present on given Cs atom it means that it is neutral in nature. Hence, number of protons and electrons present in Cs are 55.
- For Ba, it is also neutral in nature and atomic number of barium is 56. Hence, number of protons and electrons present in Ba are 56.
- For S, there is no charge on it so it is also neutral in nature. Atomic number of S is 16. Hence, number of protons and electrons present in S are 16.
Answer:
The atmosphere is 10 million times
Explanation:
Answer:
Se⁻²
Explanation:
Even though the atom is not shown, we can consult the periodic table. Selenium (Se) is in group 6 and period 4, so it has 6 valence electrons. To be stable, the atom must have a noble gas configuration with 8 valence electrons, thus, selenium must gain 2 electrons.
When an atom gain electrons, it is negatively charged, because electrons have a negative charge. So, the ion formed is Se⁻².