Answer:
9.0 g/cm³
Explanation:
Density can be computed with the formula:

Where:
D = Density
M = Mass
V = Volume
In your problem we are given:
84 cm³ = volume
760 g = mass
So we just plug in our given into the formula:



The answer would then be:
9.0 g/cm³
Answer:0.026ml
Explanation:
Details are found in the image attached. We must subtract the saturated vapour pressure of hydrogen gas at the given temperature from the total pressure of the hydrogen gas collected over water to obtain the actual pressure of hydrogen gas and substitute the value obtained into the general gas equation. The dry hydrogen gas has no saturated vapour pressure hence the value is substituted as given. All temperatures must be converted to Kelvin before substitution.
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.