Answer: 8.2
Explanation:
pH of a solution is - Log [ H+].
pH = - Log [ 6.2 x 10-9 M]
= 9 - 0.7924
pH = 8.24 approx 8.2
<span>3) P4O10 and P2O5
The mass of the P4O10 divided by the mass of the P2O5=2, and if you multiply the number of atoms in the P2O5 by 2, you get the P4O10, thus P2O5 is its empirical formula.</span>
Answer: 3 significant figures
Explanation: because in scientific notation only the before and after decimal number are considered but in standard form all numbers including exponents are all significant figures
Answer:
The molar mass of the liquid 62.89 g/mol
Explanation:
Step 1: Data given
Mass of the sample = 0.1 grams
Temperature = 70°C
Volume = 750 mL
Pressure = 0.05951 atm
Step 2: Calculate the number of moles
p*V = n*R*T
n = (p*V)/(R*T)
⇒ with n = the number of moles gas = TO BE DETERMINED
⇒ with p = The pressure = 0.05951 atm
⇒ with V = The volume of the flask = 750 mL = 0.750 L
⇒ with R = The gasconstant = 0.08206 L*atm/K*mol
⇒with T = the temperature = 70 °C = 343 Kelvin
n = (0.05951 *0.750)/(0.08206*343)
n = 0.00159 moles
Step 3: Calculate molar mass
Molar mass = mass / moles
Molar mass =0.1 gram / 0.00159 moles
Molar mass = 62.89 g/mol
The molar mass of the liquid 62.89 g/mol
Answer:
3.33 tanques de O₂
Explanation:
Basados en la reacción:
2C₂H₂(g) + 5O₂(g) → 4CO₂(g) + 2H₂O(g)
<em>2 moles de acetileno reaccionan con 5 moles de oxígeno produciendo 4 moles de dióxido de carbono y 2 moles de agua</em>
<em />
La ley de Avogadro dice que el volumen de un gas bajo temperatura y presión constantes es proporcional a las moles de este gas. Así, como 2 moles de acetileno reaccionan con 5 moles de oxígeno, los litros de O₂ necesarios para quemar 9340L de acetileno son:
9340 L C₂H₂ × (5 moles O₂ / 2 moles C₂H₂) = <em>23350L de O₂</em>
Si un tanque contiene 7x10³ L de O₂ serán necesarios:
23350L O₂ ₓ (1 tanque / 7x10³L) =<em> 3.33 tanques de O₂</em>
