Rf value is the ratio of the distance traveled by the solute to that of the solvent front on the paper used in chromatographic separation.
From the image it is clear the distance traveled by solvent front = 7.3 cm
Distance traveled by the component -1 of the mixture = 1.4 cm
Distance traveled by the component -2 of the mixture = 3.0 cm
Distance traveled by the component -3 of the mixture = 4.5 cm
Distance traveled by the component -4 of the mixture = 6.5 cm
Rf value of component-1 = 
Rf value of component-2 = 
Rf value of component-3 = 
Rf value of component-4 = 
b) Samples can be separated from a mixture using chromatography as the relative affinities for the compounds towards the paper (stationary phase) and the solvent(mobile phase) are different. Each component spends different amounts of time on the stationary phase depending on it chemical nature. So, the components in a mixture can be separated based on their polarities and relative degrees of adsorption on the stationary phase.
Answer:
34.8 moles of CO₂ are produced
Explanation:
This is the reaction:
1C₅H₁₂ + 8O₂ → 6H₂O + 5CO₂
Ratio is 1:5. We make a rule of three
1 mol of pentane can produce 5 moles of CO₂
Then, 6.96 moles of pentane may produce (6.96 .5) / 1 = 34.8 moles
Yes it can cause chemical change
The balanced reaction is
Ca + 2H2O → Ca(OH)2 + H2
Here this reaction can be compared with
A + BC ---> AB + C
So here one reactant (A) is accepting a group which is being given by another compound (BC) however the A is not giving any group / element or ion
So this single displacement
Similarly in the given reaction
the anion OH- is only being replaced
The element Ca accepts OH- and H2O loses the same group to form new element H2
So the correct answer is
Single replacement also known as single displacement