Answer:
The molality of isoborneol in camphor is 0.53 mol/kg.
Explanation:
Melting point of pure camphor= T =179°C
Melting point of sample = 
= 165°C
Depression in freezing point = 
Depression in freezing point is also given by formula:
= The freezing point depression constant
m = molality of the sample
i = van't Hoff factor
We have: = 40°C kg/mol
i = 1 ( organic compounds)
The molality of isoborneol in camphor is 0.53 mol/kg.
The given reaction is:
C4H10 + O2 → CO2 + H2O
The above equation is not balanced due to the unequal distribution of atoms on either side of equation
# atoms Reactants # atoms products
C = 4 C = 1
H = 10 H = 2
O = 2 O = 3
In order to balance it, multiply C4H10 by 2, O2 by 13, CO2 by 8 and H2O by 10 to get:
2C4H10 + 13 O2 → 8CO2 + 10H2O
<u>Analysing the Question:</u>
We are given a 250 mL solution of 0.5M K₂Cr₂O₇
Which means that we have:
0.5 Mole in 1L of the solution
0.125 moles in 250 mL of the solution <em>[dividing both the numbers by 4]</em>
<em />
<u>Mass of K₂Cr₂O₇ in the given solution:</u>
Molar mass of K₂Cr₂O₇(Potassium Dichromate) = 194 g/mol
<em>we know that we have 0.125 moles in the 250 mL solution provided</em>
Mass = Number of moles * Molar mass
Mass = 0.125 * 194
Mass = 36.75 grams
The substance which has definite composition with definite physical and chemical properties is said to be pure substance. These substances are not separated by the different physical techniques such as filtration, distillation, evaporation etc.
The clear water pumped from a deep aquifer is a pure substance because water is a pure compound which consist of constant single type of atoms or group of atoms and water has specific value of boiling and melting point. Water is also not separated into units or constituents by physical technique.
Hence, clear water pumped from a deep aquifer is a pure substance.
