The purpose of using distilled water in the cuvette of the spectrophotometer is to calibrate the instrument. It is generally considered that distilled water shows zero absorbance and 100 % transmittance. So, to zero out the absorbance of compounds other than the analyte being determined, distilled water is used as a blank.
If the unknown being determined is prepared using ethanol as the base solution, the blank used must be ethanol. This is because absorbance if any from the solvent, ethanol must be zeroed out as when the measurement of the actual unknown is being made, the absorbance of the solvent does not interfere.
Answer:
The answer to your question is below
Explanation:
a) HCl 0.01 M
pH = -log [0.01]
pH = - (-2)
pH = 2
b) HCl = 0.001 M
pH = -log[0.001]
pH = -(-3)
pH = 3
c) HCl = 0.00001 M
pH = -log[0.00001]
pH = - (-5)
pH = 5
d) Distilled water
pH = 7.0
e) NaOH = 0.00001 M
pOH = -log [0.00001]
pOH = -(-5)
pH = 14 - 5
pH = 9
f) NaOH = 0.001 M
pOH =- log [0.001]
pOH = 3
pH = 14 - 3
pH = 11
g) NaOH = 0.1 M
pOH = -log[0.1]
pOH = 1
pH = 14 - 1
pH = 13
Answer:
A. It formed by barium(Ba+2) ion and sulfate ( SO42- )
B. It is formed by calcium ion (Ca+2) and two fluoride ions (2F-)
C. It is formed by magnesium ion (Mg+2) and nitride ion (N3-)
D. It is formed by two potassium ions (2 K+) and oxide ion(O2-)
Answer:
See explaination
Explanation:
The invariant mass of an electron is approximately9. 109×10−31 kilograms, or5. 489×10−4 atomic mass units. On the basis of Einstein's principle of mass–energy equivalence, this mass corresponds to a rest energy of 0.511 MeV.
Check attachment for further solution to the exercise.
A. Smell (Oder) B. Color and D I’m pretty sure because the common properties are Color, Oder, Melting point, and boiling point
