The force upon a moving object
The equation Eºcell = 0.0592/n logK must be used to find n and also Eºcell
2 Al(s) + 3 Mg2+(aq) → 2 Al3+(aq) + 3 Mg(s) Al3+ +3e- --> Al Eº = -1.66 V Mg2+ +2e- -->Mg Eº = -2.37V
To balance the equation, 6 moles of electrons must be transferred (2 Al and 3 Mg). This will be the value of n in the equation.
To find Eºcell, you need the reduction potentials which should be given in a table, and given above. Eºcell = -1.66 - (-2.37) = 0.71 V log K = Eºcell x n/0.0592 = 0.71 x 6/0.0592 log K = 71.95 K = 10^71.95 K = 1.1x10^72
PH of a solution will be <span>higher than 7
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Ammonium cyanide is a salt formed by hydrogen cyanide and ammonia. Ammonia is a weak base and hydrogen cyanide is a weak acid.
NH₄CN + H₂O ⇒ NH₃ + HCN
NH₄⁺ + H₂O -----> H₃O⁺ + NH₃
CN⁻ + H₂O -----> HCN + OH⁻
Although both compounds are weak electrolytes, NH₃ is somewhat stronger base than HCN is a strong acid, so the solution reacts alkaline. We can prove this using Ka and Kb values:
Ka(HCN) = 4.9 x × 10⁻¹⁰
Kb(NH₃) = 1.8 × 10⁻⁵<span>
Kw= </span>1.0 × 10⁻¹⁴
Let's first calculate Ka for NH₄⁺:
Ka(NH₄⁺) x Kb(NH₃<span>) = pKw
</span>Ka(NH₄⁺) = Kw/Kb(NH₃) = 5.6 x 10⁻¹⁰
Then, Kb for CN⁻:
Kb(CN⁻) x Ka(HCN) = pKw
Kb(CN⁻) = Kw/Ka(HCN) = 2 x 10⁻⁵
From this, we can see that the acid constant NH4⁺ is much lower than the base constant of CN⁻, which will say that the solution of NH₄CN will react slightly alkaline because of the higher presence of hydroxyl ions in solution.
Answer:
mm = 1043.33 g/mol
Explanation:
osmotic pressure (π):
∴ π = 17.8 torr = 0.0234 atm
∴ Cb: solute concentration
∴ T = 25°C = 298 K
∴ R = 0.082 atm.L/K.mol
⇒ Cb = π/RT
⇒ Cb = (0.0234 atm)/((0.082 atm.L/K.mol)(298 K))
⇒ Cb = 9.585 E-4 mol/L
molar mass (mm):
⇒ mm = (1.00 g/L)(L/9.585 E-4 mol)
⇒ mm = 1043.33 g/mol
Answer:
D. 4
Explanation:
Answer and Explanation: Carbon can form a maximum of four covalent bonds. Carbon can share up to four pairs of electrons, therefore, the carbon atom fills its outer energy level and achieves chemical stability.
