Answer;
c.electrons move from the wool to the rod.
Explanation;
-Atoms are generally neutral (have the same number
of protons as electrons). Substances lose electrons to become
positively charged, while other substances gain electrons to become negatively charged.
-When a plastic rod is rubbed with woolen
cloth or wool, a transfer of electrons occurs (from the wool to the rod). The rod gains electrons; thus, it
is negatively charged.
Answer:
Yes.
Explanation:
Yes, the change in cuvette lead to a determinate error in the analysis if the different cuvette is used for the analysis because the amount of liquid sample that is used has different volume. If both cuvette are of the same type and has no difference in their structure and size then there is error occurs in the analysis but if both cuvette are different from one another then the error will occur in the analysis. because the amount of liquid that is used has different volume.
This is the three cases that help to determine the minimum concentration of KOH required for precipitation
Part a) 1.5×10^−2 M K CaCl2
Part b) 2.3×10^−3 M Fe (NO3)2
Part c) 2.0×10^−3 M MgBr2
a) CaCl2 + 2KOH --> Ca (OH) 2 + 2KCl Ca (OH) 2 <=> Ca^2+ + 2OH^-
ksp = 1.5*10^-2 + x^2
4.68*10^-6 = 1.5*10^-2 + x^2
x= [KOH] = 0.01766
b) Fe (NO3)2 +2 KOH--> Fe (OH)2 + 2KNO3
Fe (OH)2 <=> Fe^2+ + 2OH^-
ksp = 2.3*10^-3 + x^2
4.87*10^-17 = 2.3*10^-3 + x^2
x= 1.46*10^-7
c) MgBr2 + KOH --> Mg (OH) 2 + 2KBr
Mg (OH) 2 <=> Mg^2+ + 2OH^-
ksp = 2.0*10^-3 + x^2
2.06*10^-13 = 2.0*10^-3 + x^2
x= 1.015*10^-5
After one half-life, one half is remaining. After two half-lives one fourth is remaining. So that would be 25%
yes 89.75 sorry I'm not the best at math you should look on the internet
