Answer:
1. 192.0 g/mol.
2. 84.0 g/mol.
Explanation:
- The molar mass refers to the weight of all atoms combined in a molecule measured in grams per mole.
- To find a molecule's molar mass, we begin by looking up the atomic weights of the relevant elements from the periodic table. Next, we tally the atoms present and multiply that by their respective atomic weights.
1. Molar mass of citric acid (C₆H₈O₇):
Molar mass of C₆H₈O₇ = 6(atomic mass of C) + 8(atomic mass of H) + 7(atomic mass of O) = 6(12.0 g/mol) + 8(1.0 g/mol) + 7(16.0 g/mol) = 192.0 g/mol.
2. Molar mass of baking soda (NaHCO₃):
Molar mass of NaHCO₃ = (atomic mass of Na) + (atomic mass of H) + (atomic mass of C) + 3(atomic mass of O) = (23.0 g/mol) + (1.0 g/mol) + (12.0 g/mol) + 3(16.0 g/mol) = 84.0 g/mol.
Answer: The net ionic equation is 
Explanation:
A double displacement reaction involves the exchange of ions. Chemicals that dissolve in water are marked with the symbol (aq), while those that do not dissolve and remain solid are shown with (s) after their formulas.
The ion-based representation of the equation is:
"Spectator ions" are the ions that do not participate in the chemical reaction, appearing on both sides of the equation in ionic form.
Ammonium and chlorate ions are present on both sides; thus, they do not factor into the net ionic equation.
Therefore, the net ionic equation is:
<span>The partial pressure of oxygen is 438.0 mmHg. The ideal gas equation is expressed as PV = nRT where P represents pressure, V denotes volume, n is the number of moles, R is the ideal gas constant (8.3144598 (L*kPa)/(K*mol)), and T signifies absolute temperature. To convert from Celsius to Kelvin, we have 43.4 + 273.15 = 316.55 K. For the pressure conversion from mmHg to kPa: 675.9 mmHg * 0.133322387415 = 90.11260165 kPa. When solving for n using the ideal gas equation, we derive n = PV / (RT) which provides n = 90.11260165 kPa * 16.2 L / (8.3144598 (L*kPa)/(K*mol) * 316.55 K)= 1459.824147 L*kPa / 2631.94225 (L*kPa)/(mol), resulting in n = 0.554656603 mol. Thus, we have 0.554656603 moles of gas particles. Next, we determine the contribution from oxygen. The atomic weight of oxygen is 15.999 g/mol, while argon is 39.948 g/mol, and the molar mass of O2 is 31.998 g/mol. We establish the relationships where M is the number of moles of O2, and 0.554656603 - M gives the number of moles of Ar. Setting up the equation: M * 31.998 + (0.554656603 - M) * 39.948 = 19.3, we solve for M resulting in 0.359424148 moles of oxygen out of 0.554656603 total moles. This leads to oxygen providing 0.359424148 / 0.554656603 = 0.648012024 or 64.8012024% of the total pressure of 675.9 mmHg. The partial pressure therefore calculates to 675.9 * 0.648012024 = 437.9913271 mmHg, rounded to 438.0 mmHg</span>
Response:
The pKa value is 13.0.
Clarification:
pKa + pKb = 14
For trimethylamine, Kb = 6.3 × 
Calculating pKb: pKb = - log (6.3 × )
= 1.0
Thus, pKa = 14 - pKb = 14 - 1.0
pKa = 13.0
Verification: The typical range for pKa in weak acids is from 2 to 13.
Respuesta:
El oxígeno en H2O2 es la especie que se reduce a H2O y se oxida a O2.
Explicación:
5 H2O2(aq) + 2 MnO4-(aq) + 6 H+(aq) → 2 Mn2+(aq) + 8 H2O(l) + 5 O2(g)
La oxidación se define como la pérdida de electrones. La oxidación provoca un aumento en el número de oxidación de un elemento.
Si se descompone esta reacción en sus mitades de reducción y oxidación
Se observa que, de los reactivos mencionados anteriormente,
H202 se convierte en H2O y O2
MnO4- + H+ se convierte en Mn2+ y H2O
El número de oxidación de Mn cambia de +7 en MnO4- a +2 en Mn2+ (lo que indica evidentemente una reducción)
El oxígeno en MnO4- no cambia su número de oxidación, ya que se mantiene en -2
El número de oxidación del oxígeno cambia de -1 en H2O2 a -2 en H2O y 0 en O2
El hidrógeno en H2O2 no cambia su número de oxidación, y su número de oxidación se mantiene en +1 tanto en H2O2 como en H2O.
Esto indica que H2O2 sufre tanto oxidación como reducción; más específicamente, el oxígeno en H2O2 es la especie que se reduce a H2O y se oxida a O2.
Espero que esto ayude
