Answer:
c) 387g
Explanation:
Water;
Mass = 250g
Specific heat = 4.184
Initial Temp, T1 = 25 + 273 = 298K
Final Temp, T2 = 35 + 273 = 308K
Heat = ?
H = mc(T2 - T1)
H = 250 * 4.184 (308 - 298)
H = 10460 J
Iron;
Initial Temp, T2 = 95 + 273 = 368K (Upon converting to kelvin temperature)
Mass = ?
Final Temp, T1 = 35 + 273 = 308
Heat = 10460 (Heat lost by iron is qual to heat gained by water)
Specific heat = 0.45
H = mc(T2-T1)
M = 10460 / [0.45 (308 - 368)]
M = 10460 / 27
M = 387g
Answer and Explanation:
The resonance contributor in cyclopentadienone (as shown in the attachment below) results into the compound having a positive charge on the carbonyl group, C=O which accounts for a highly reactive anti-aromatic 4π system. And this illustrates the reason for its instability.
C. Chemical properties always change depending on temperature or pressure
Correct Answer: option <span>(1) Mn(s)
Reason:
The </span><span>spontaneity of electrochemical cell, depends on the it's Eo value. Electrochemical cells with positve Eo are spontanous and vice-versa.
</span>
In present case, the Eo of half-cell of interest are as follows:
Eo Zn2+/Zn = <span>-0.763v
</span>Eo Mg2+/Mg = 2.37v
Eo Mn2+/Mn = -1.18v
Therefore, Eo cell (with Zn as one of the half-cell) = Eo Zn2+/Zn - Eo Mn2+/Mn
= -0.763 - (-1.18)
= 0.417v
On other hand, Eo cell (with Mg as one of the half-cell) = Eo Mg2+/Zn - Eo Mn2+/Mn
= -2.37 - (-1.18)
= -1.19v
Thus, Mn(s) <span>metal will spontaneously react with Zn2+(aq), but will not spontaneously react with Mg2+(aq)</span>
