The fossil could get damaged and broken into smaller pieces. That is a way it could make it difficult to determine the fossils age.
Answer: A
Explanation: Calculate the molar hydrogen ion concentration of each of the following biological solutions given the pH, Urine pH= 4.90
Explanation:
The given data is as follows.
Refractive index of mixture = 1.456
Refractive index of hexane = 1.375
Refractive index of toulene = 1.497
Let mole fraction of hexane =
and, mole fraction of toulene =
Also, 
or, 
Hence, calculate the mole fraction of hexane as follows.
refractive index mixture= mole fraction hexane × ref index hexane + mole fraction toluene × ref index toluene.
1.456 = 
1.456 = 
0.081 = 
= 
= 0.66
Since, 
= 1 - 0.66
= 0.34
Thus, we can conclude that mole fraction of hexane in your sample is 0.34.
Answer : The mass of ethylene glycol is, 437.34 grams
Solution : Given,
Volume of ethylene glycol = 394 ml
Density of ethylene glycol = 1.11 g/ml (Standard value)
Formula used :

Now put all the given values in this formula, we get the mass of ethylene glycol.


Therefore, the mass of ethylene glycol is, 437.34 grams