You are eating a pizza. What type of mixture are you consuming?

Why did you blank with the 0.0020 M Fe(NO3)3 solution as opposed to just DI water? What does it do to your spectrum? What chemic

Vlad1618 [11]

Answer:

The cuvette was blank with the solution so that the spectrometer will only read the solute absorbance. This also ensures that the spectrometer will ignore other absorbance fluctuations that normally occur due to the chemical make-up of water. The spectrometer only considered the absorbance of $FeNCS^{2+}$ as indicated on the spectrum. The reaction between the $Fe^{3+}$ and the $SCN^{-}$ are both clear liquids that form the orange liquid product $FeNCS^{2+}$ which creates the absorbance spectrum. Because the color of the solution is orange, it reflects this and similar colors while absorbing blueish hues. We can find the absorption of only the $FeNCS^{2+}$ by pre-rinsing the cuvette with each solution we intend to measure before placing it in the spectrometer. Also, wipe each cuvette with a kimwipe to remove all fingerprints that could effect the data collection.

Explanation:

The cuvette was blank with the solution so that the spectrometer will only read the solute absorbance. This also ensures that the spectrometer will ignore other absorbance fluctuations that normally occur due to the chemical make-up of water. The spectrometer only considered the absorbance of $FeNCS^{2+}$ as indicated on the spectrum.

3 0

1 year ago

A 2.550 x 10^−2 M solution of glycerol (C3H8O3) in water is at 20.0°C. The sample was created by dissolving a sample of C3H8O3 i

BARSIC [14]

Answer:

$2.557\times 10^{-2}\ molal.$

Explanation:

Given , molarity of glycerol= $2.55\times 10^-^2\ M.$

Volume= 1 L.

Therefore, No of moles of glycerol= $molarity\times volume\ in\ liters=2.55\times 10^-^2\ moles.$

Now, volume of water needed, V=998.8 mL.

Density is given as= 0.9982 g/mL.

Therefore, mass of water = $volume\times density=998.8\times 0.9982=997\ g=0.997\ kg$

Now, molality= $\dfrac{no\ of\ moles}{mass\ of\ solvent\ in\ kg}=\dfrac{2.55\times 10^-^2\ }{0.997}=0.02557\ molal=2.557\times 10^{-2}\ molal.$

Hence, this is the required solution.

3 0

1 year ago

In a chemistry lab, you have two vinegars. one is 5% acetic acid, and one is 6.5% acetic acid. you want to make 200 ml of a vine

nexus9112 [7]

Assume that the amount needed from the 5% acid is x and that the amount needed from the 6.5% acid is y.

We are given that:
The volume of the final solution is 200 ml
This means that:
x + y = 200
This can be rewritten as:
x = 200 - y .......> equation I

We are also given that:
The concentration of the final solution is 6%
This means that:
5%x + 6.5%y = 6% (x+y)
This can be rewritten as:
0.05 x + 0.065 y = 0.06 (x+y) ............> equation II

Substitute with equation I in equation II and solve for y as follows:
0.05 x + 0.065 y = 0.06 (x+y)
0.05 (200-y) + 0.065 y = 0.06 (200-y+y)
10 - 0.05 y + 0.065 y = 12
0.015y = 12-10 = 2
y = 2/0.015
y = 133.3334 ml

Substitute with the y in equation I to get the x as follows:
x = 200 - y
x = 200 - 133.3334
x = 66.6667 ml

Based on the above calculations:
The amount required from the 5% acid = x = 66.6667 ml
The amount required from the 6.5% acid = y = 133.3334 ml

Hope this helps :)

6 0

2 years ago

Read 2 more answers

Write chemical equations and corresponding equilibrium expressions for each of the two ionization steps of carbonic acid. Part A

lesantik [10]

<u>Answer:</u> The chemical equations and equilibrium constant expression for each ionization steps is written below.

<u>Explanation:</u>

The chemical formula of carbonic acid is $H_2CO_3$ . It is a diprotic weak acid which means that it will release two hydrogen ions when dissolved in water