It is an example of a physical change because the chocolate changes from a solid to a liquid however it’s chemical composition is not changed so it’s a physical change.
True, biodiversity creates different species animals depend on each other for food and other reasons so the answer is true.
Answer: -
Baking soda having a pH of 9, has the maximum number of hydroxide ions.
Explanation: -
More the pH of a solution, the more basic it is and more the number of hydroxide ions it has.
From the question we find that
baking soda has a pH = 9
milk has a pH = 6
tomato juice has a pH = 3.5
vinegar has a pH = 2
Thus among them baking soda has the highest pH.
So baking soda is the most basic and has the maximum number of hydroxide ions.
Answer:
ε = 201.5
Explanation:
Given data-
mass of benzene = 25.8 mg
= 25.8×10^-3 kg
Atomic mass of benzene= 78.11 amu
volume of hexane = 250.00 ml = 0.2500 L
Absorbance = 0.266
Length of the cell = 1.00 cm
Hence concentration =
solving we get
= 0.00132 M
Formula:
A= εcl
A= absorbance
c= concentration and l= length of cell
now substituting values in the above formula
0.266= ε×0.00132×1.000
⇒ε =
⇒ε = 201.5