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3 years ago

1 How is the density of a substance calculated?

Chemistry

1 answer:

user100 [1]3 years ago

4 0

Sorry for the scribbles lol

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In acid solution, water can add to the double bond of 2-butenedioic acid to form 2-hydroxysuccinic acid.

satela [25.4K]

So, what is the question?

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2 years ago

Th e molar absorption coeffi cient of a substance dissolved in water is known to be 855 dm3 mol−1 cm−1 at 270 nm. To determine t

Olegator [25]

Answer : The percentage reduction in intensity is 79.80 %

Explanation :

Using Beer-Lambert's law :

$A=\epsilon \times C\times l$

$A=\log \frac{I_o}{I}$

$\log \frac{I_o}{I}=\epsilon \times C\times l$

where,

A = absorbance of solution

C = concentration of solution = $3.25mmol.dm^{3-}=3.25\times 10^{-3}mol.dm^{-3}$

l = path length = 2.5 mm = 0.25 cm

$I_o$ = incident light

$I$ = transmitted light

$\epsilon$ = molar absorptivity coefficient = $855dm^3mol^{-1}cm^{-1}$

Now put all the given values in the above formula, we get:

$\log \frac{I_o}{I}=(855dm^3mol^{-1}cm^{-1})\times (3.25\times 10^{-3}mol.dm^{-3})\times (0.25cm)$

$\log \frac{I_o}{I}=0.6947$

$\frac{I_o}{I}=10^{0.6947}=4.951$

If we consider $I_o$ = 100

then, $I=\frac{100}{4.951}=20.198$

Here 'I' intensity of transmitted light = 20.198

Thus, the intensity of absorbed light $I_A$ = 100 - 20.198 = 79.80

Now we have to calculate the percentage reduction in intensity.

$\% \text{reduction in intensity}=\frac{I_A}{I_o}\times 100$

$\% \text{reduction in intensity}=\frac{79.80}{100}\times 100=79.80\%$

Therefore, the percentage reduction in intensity is 79.80 %

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3 years ago

trial 2, 2.68 g/cm/3 trial 3, 2.84g/cm/3. aluminum has a density of 2.70g/cm/3 calcute the percent error for each trial.

serg [7]

Answer:

trial 2: 0.74

trial 3: 5.19

I think but the equation for sloving percent error is:

(true value - determined value)/true value * 100

Explanation:

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3 years ago

What is the correct order of earths six convection cells , from the North Pole to the South Pole

makkiz [27]

<span>polar, Hadley, Ferrel, polar, Hadley, Ferrel. I hope this helps you.</span>

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2 years ago

Write a balanced chemical equation for the standard formation reaction of solid sodium orthosilicate

Mumz [18]

Equation for the standard formation of solid sodium orthosilicate:
4 Na(s) + Si(s) + 2 O₂(g) → Na₄SiO₄(s)

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3 years ago

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