Answer:
A. K
Step-by-step explanation:
Remember the trends in the Periodic Table:
- Atomic radii <em>decrease</em> from left to right across a Period.
- Atomic radii <em>increase</em> from top to bottom in a Group.
- Ionic radii of metal cations are <em>smaller</em> than those of their atoms.
Thus, the largest atoms are in the lower left corner of the Periodic Table.
The diagram below shows that K is closest to the lower left, so it is the largest atom. It is also larger than any of the cations.
The mass of Hydrogen is 2 g/mol
The mass of Helium is 4 g/mol
The anode is the electrode where the oxidation occurs.
Cathode is the electrode where the reducction occurs.
Equations:
Mn(2+) + 2e- ---> Mn(s) Eo = - 1.18 V
2Fe(3+) + 2e- ----> 2 Fe(2+) 2Eo = + 1.54 V
The electrons flow from the electrode with the lower Eo to the electrode with the higher Eo yielding to a positive voltage.
Eo = 1.54 V - (- 1.18) = 1.54 + 1.18 = 2.72
Answer: 2.72 V
Data Given:
Pressure = P = ?
Volume = V = 3.0 L
Temperature = T = 115 °C + 273 = 388 K
Mass = m = 75.0 g
M.mass = M = 44 g/mol
Solution:
Let suppose the Gas is acting Ideally. Then According to Ideal Gas Equation,
P V = n R T
Solving for P,
P = n R T / V ------ (1)
Calculating Moles,
n = m / M
n = 75.0 g / 44 g.mol⁻¹
n = 1.704 mol
Putting Values in Eq. 1,
P = (1.704 mol × 0.08205 atm.L.mol⁻¹.K⁻¹ × 388 K) ÷ 3.0 L
P = 18.08 atm
