Answer:
6.9 ml of concentrate
Explanation:
100 ml of .1 M will require .01 moles
from a 1.45 M solution, .01 mole would be
.01 mole / ( 1.45 mole / liter) = 6.9 ml of the concentrate then dilute to 100 ml
H3PO4 has molecular weight of approximately 98 grams per
mole. 4.50 M is equal to 4.50 mole per 1000 mL solution of H3PO4. 255 mL times
4.50 mol /1000 mL times 98 g/mol is equal to 112.455 grams. Note that I
automatically equate 1 Liter to 1000 mL since the given volume is in mL for
easier computation.
Answer:
When the water is mixed with water at lower temperature the effective temperature of the system (i.e the water at lower temperature) will increase, thereby increasing it's entropy
Explanation:
The answer that "the entropy will is increases" is correct as:
The water at 90° C i.e at higher temperature is mixed with the water at 10° C i.e the water at the lower temperature.
The water at lower temperature will have molecules with lower energy while the water with higher temperature will have molecules undergoing high thermal collisions. Thereby, when the water is mixed with water at lower temperature the effective temperature of the system (i.e the water at lower temperature) will increase, thereby increasing it's entropy.
Therefore, the answer is correct with respect to the water at lower temperature.
Meanwhile, for the water at higher temperature , the temperature of the system will decrease. Thus, the entropy of the water at higher level will decrease.
I believe the answer is B!
