Answer:
Molality = 1.13 m
Explanation:
Molality is defined as the moles of the solute present in 1 kilogram of the solvent.
Given that:
Mass of 
= 26.5 g
Molar mass of = 32.04 g/mol
The formula for the calculation of moles is shown below:
Thus,
Mass of water = 735 g = 0.735 kg ( 1 g = 0.001 kg )
So, molality is:
<u>Molality = 1.13 m</u>
Moles of K = 32.4/39 = 0.83 mole. According to stoichiometry, 2 moles of K produces 1mole of H2. Therefore, 0.83 mole of K produces = 0.83/2 = 0.415 moles of H2. Therefore number molecules of H2 = moles of H2 x 6.02 x 10^23 = 2.4983 x 10^23 molecules. Hope this helps!
Answer:
Amy can apply the Tyndall Beam effect ,by shining a beam of light through the sample solution.
Explanation:
The chemical test for starch is add iodine solution to the tested sample which is yellow/brown and observe the color change to blue/black color. However, the physical test to distinguish simple sugars from starch is the shine a beam of light through the sample solution. Because that sample solution contained no simple sugars, then the presence of starch in the solution will be indicated by dispersal of light because the large starch molecules are enough to affect the light.
