Answer:
Both K+ and NO3- concentrations are halved
Explanation:
Since the reaction is
K₂Cr₂O₇ + Pb(NO₃)₂ 2K(NO₃) + <u>PbCr</u>₂<u>O</u>₇
knowing that K+ and NO3- are spectator ions, their concentration do not change due to reaction but it will change due to the mixing of volumes of the reactants since we are mixing volumes of different concentrations.
for K+ initially we have:
c K+ initial = 0.25 M
c K+ final = n/ V = C i * Vin / Vfinal = 0.25 M * 100 ml / 200 ml = 0.125 M
the 200 ml comes from mixing the 100 ml of Pb(NO₃)₂ and 100 ml of K₂Cr₂O₇ ( assuming that the volume of the precipitate is insignificant relative to the solution , it does not occlude a significant portion of the saturated solution and assuming that any volume contraction/expansion due to non ideal behaviour of the solution is negligible)
the same happens with NO3- ,therefore its concentration is also halved
Mg has similar properties to barium
Answer:
For A = 733.2 torr
For B = 740.1 torr
Explanation:
Given data:
For A
Height = 15.4 mm
Pressure of atmosphere = 0.985 atm ( 0.985 ×760 = 748.6 mmHg)
Pressure of gas = ?
For B
Height = 12.3 mm
Pressure of atmosphere = 0.99 atm ( 0.99×760 = 752.4 mmHg)
Pressure of gas = ?
Solution:
For A
P( gas) = P (atmosphere) - 15.4 mmHg
P( gas) = 748.6 mmHg - 15.4 mmHg
P( gas) = 733.2 mmHg or 733.2 torr
For B
P( gas) = P (atmosphere) - 12.3 mmHg
P( gas) = 752.4 mmHg - 12.3 mmHg
P( gas) = 740.1 mmHg
or
740.1 torr
Dome volcano will form I’m pretty sure
I think this answer is D or C
