1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
nadezda [96]
3 years ago
15

What was the purpose of putting distilled water in the blank cuvette? if your unknown used ethanol as the base solvent, what wou

ld the blank consist of?
Chemistry
1 answer:
Margaret [11]3 years ago
7 0

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.

You might be interested in
Ammonia (NH3) burns in air to form nitrogen dioxide and water. Calculate grams of nitrogen dioxide produced if 4.0 grams of ammo
kenny6666 [7]
The balanced equation for the above reaction is;
4NH₃ + 7O₂  --> 4NO₂  + 6H₂O
stoichiometry of NH₃ to NO₂ is 4:4
the number of NH₃ moles consumed are - 4.0 g / 17 g/mol = 0.24 mol
number of NH₃ moles reacted are equivalent to number of NO₂ moles formed 
therefore number of NO₂ moles formed - 0.24 mol x 46 g/mol = 11.04 g
mass of NO₂ formed is 11.04 g
8 0
3 years ago
9) All elements can be sorted into 3 simple groups:
serious [3.7K]

Answer: B) metals, non-metals, metalloids

An example of a metal is iron. A non-metal example is oxygen, which is a gas at STP (standard temperature and pressure).

A metalloid is a bit of a mix between a metal and non-metal element. It's sorta like an element that has both properties of metals and non-metals, or it's in a murky gray area. An example of a metalloid would be silicon.

6 0
2 years ago
Read 2 more answers
The three beakers shown below contain solutions of [cof6]3–, [co(nh3)6]3+, and [co(cn)6]3–. based on the colors of the three sol
vitfil [10]
[Co(CN)₆]³⁻ → Yellow
[Co(NH₃)₆]³⁺ → Orange
[CoF₆]³⁻ → Blue
Explanation:
- All the given compounds have octahedral geometry but the ligand in each are different with the same metal ion.

- Ligands strength order:     CN⁻ > NH₃ > F⁻ 

- The ligand CN will act as a strong field ligand so that the splitting is maximum when compared to NH₃ and F⁻

- If the splitting is more, the energy required for transition is more, and the wavelength is inversely proportional to energy.

- So CN complex will absorb at lower wavelength (yellow color)
3 0
3 years ago
A mole of cars stacked end to end would stretch back and forth across the United States how many times? Measured length of 1 car
vekshin1

Answer:

i am potato

Explanation:

4444141+5-45458/85*55474

3 0
2 years ago
Elimination of the pharmaceutical IV antibiotic gentamicin follows first-order kinetics. If the half-life of gentamicin is 1.5 h
Genrish500 [490]

Explanation:

The given data is:

The half-life of gentamicin is 1.5 hrs.

The reaction follows first-order kinetics.

The initial concentration of the reactants is 8.4 x 10-5 M.

The concentration of reactant after 8 hrs can be calculated as shown below:

The formula of the half-life of the first-order reaction is:

k=\frac{0.693}{t_1_/_2}

Where k = rate constant

t1/2=half-life

So, the rate constant k value is:

k=\frac{0.693}{1.5 hrs}

The expression for the rate constant is :

k=\frac{2.303}{t} log \frac{initial concentration}{concentration after time "t"}

Substitute the given values and the k value in this formula to get the concentration of the reactant after time 8 hrs is shown below:

\frac{0.693}{1.5 hrs} =\frac{2.303}{8 hrs} x log \frac{8.4x10^-^5}{y} \\ log \frac{8.4x10^-^5}{y} =1.604\\\frac{8.4x10^-^5}{y}=10^1^.^6^0^4\\\frac{8.4x10^-^5}{y}=40.18\\y=\frac{8.4x10^-^5}{40.18} \\=>y=2.09x10^-^6

Answer: The concentration of reactant remains after 8 hours is 2.09x10^-6M.

5 0
3 years ago
Other questions:
  • A typical aspirin tablet contains 327 mg of acetylsalicylic acid, HC9H7O4. Calculate the pH of a solution that is prepared by di
    9·1 answer
  • Which blood glucose-lowering hormones is produced by the pancreatic islet cells
    6·1 answer
  • Your sense of touch is based in your _____.<br> bones<br> muscles<br> skin<br> tissues
    13·1 answer
  • At high temperatures, steam decomposes into its elements according to the following equation.
    11·2 answers
  • Match the formula for the following compound: 
    7·2 answers
  • A 0.7 ft diameter hole forms in a tank containing butane at 19 atmg and 76 degrees Fahrenheit. Determine the maximum possible ma
    12·1 answer
  • Need help on this fast ​
    7·2 answers
  • PLS HELP WILL GIVE BRAINLYEST What happens when the magnet is removed from the coil in a circuit?
    14·1 answer
  • Plz help..........................
    12·1 answer
  • Tính thể tích ở điều kiện tiêu chuẩn của một hỗn hợp khí gồm 4,4g CO2 và 3,2g O2. Tính số mol trong 3.10^23 phân tử nước
    15·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!