Answer is: a) in the presence of a base.
Phenolphthalein is colorless in acidic solutions and pink in basic solutions.
Acid-base indicators are usually weak acids or bases and they are chemical detectors for hydrogen or hydronium cations.
Example for acid-base indicator is phenolphthalein (molecular formula C₂₀H₁₄O₄).
When solution turns phenolphthalein pink, it means it is basic (pH>7).
The brick is solid because it's not hollow or containing spaces or gaps
Answer:
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Answer:
A. Generally ionic compounds are formed metal and non metal elements since they forms opposite charged ions due to difference in their Electronegativity values.
NaCl, MgCl2, Ca(OH)2 etc are ionic compounds.
B. Generally transition elements (D elements) forms cations with different charges or simply they exist in different oxidation states due to availability of empty d orbitals.
Examples are Iron exsits as Fe+2 and Fe+3
Mn exists as Mn+2 , Mn+4, Mn+6 ,Mn+7 etc.
Answer:It would depend on the eluent solvent what we use ,If we would use a polar solvent than B will be appear first followed by c and then A on the chromatography strip.
If we use non-polar eluent solvent than A will be separated first followed by C and thenB on the chromatography strip.
Explanation:
Separation using paper chromatography is dependent upon the polarity of various pigments .
A polar pigment would move ahead in case of polar solvent used and a non-polar pigment would move ahead when we use a non-polar solvent.
So separation would occur in order of polarity of various pigments in a given solvent.
The amount of distance travelled by each component (or pigment or spot) can be calculated using the formula for retention factor:
Rf= Distance travelled by pigment spot or solute/Distance travelled by eluent solvent
Rf= Retention factor
Retention factor is basically the ratio of distance tarvelled by the pigment or spot to the ratio of distance travelled by the solvent.
