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3 years ago

Please help!! I think this is true but I really need help.

1 answer:

8 0

False, because generally forensics collect the evidence to make sure the evidence doesn’t get damaged or tainted.... hope this helps

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CHCl3 has how many double bonds?

Nonamiya [84]

Answer:

It has two sigma bonds ( the single bonds between each H and C) plus one pi bond and one sigma bond that consitute the double bond between C and O. It contains three covalent bonds, one . Hydrogen Bond Donor Count: 0: Computed by Cactvs 3.4.

Explanation:

Hope it helps you!

8 0

3 years ago

Calcium oxide is used to remove the pollutant SO2 from smokestack gases. The overall reaction is:

fgiga [73]

This problem is providing a chemical reaction reaction at equilibrium and its pressure-based equilibrium constant, and thus asks for molecules of SO2 at equilibrium. At the end, the answer turns out to be 1.25x10¹² molecules.

<h3>Chemical equilibrium</h3>

In chemistry, when chemical reactions take place, they do not necessarily go to completion, but can reach a constant-concentration point denominated "equilibrium" where the reaction does not proceed any longer.

In such a way, for the given reaction, one can write the equilibrium expression based on the law of mass action, which sets the products on top, reactants on bottom and ignores both solids and liquids:

$Kp=\frac{1}{p_{SO_2}*p_{O_2}^{1/2}}$

However, in order to calculate this, one needs the partial pressure of O2, defined in similar problems as 0.21 atm for us to find the partial pressure of SO2 first:

$2.38x10^{15}=\frac{1}{p_{SO_2}*(0.21)^{1/2}}\\\\p_{SO_2}=\frac{1}{(2.38x10^{15})(0.21)^{1/2}}\\\\p_{SO_2}=9.17x10^{-16}atm$

Keep in mind this 0.21 atm may vary depending on the problem you were given.

Thus, we obtain the mole fraction of SO2 as follows:

$x_{SO_2}=\frac{9.17x10^{-16}atm}{9.17x10^{-16}atm+0.21atm}=4.37x10^{-15}\\ \\$

Finally, we use this mole fraction to calculate the moles of SO2 in 475 moles of the gas mixture, and then use the Avogadro's number to calculate the molecules:

$molecules=475mol*4.37x10^{-15}*\frac{6.022x10^{23}}{1mol} =1.25x10^{12}molecules$

Learn more about chemical equilibrium: brainly.com/question/26453983

6 0

3 years ago

BRAINLIESIT IF CORRECT<br><br><br><br><br><br> 4

Zarrin [17]

Answer:

the answer is vacum of space

3 0

3 years ago

Read 2 more answers

If the pka of hcho2 is 3.74 and the ph of an hcho2/nacho2 solution is 3.89, it means that

Andrei [34K]

Hi, the question has some missing part. The complete question should be " If the $pK_{a}$ of $HCHO_{2}$ is 3.74 and the pH of an $HCHO_{2}/NaCHO_{2}$ solution is 3.89, it means that -

(a) $[HCHO_{2}]=[NaCHO_{2}]$

(b) $[HCHO_{2}]> [NaCHO_{2}]$

(c) $[HCHO_{2}]< [NaCHO_{2}]$

Which of the options are true?"

Answer: Option (c) is true.

Explanation:

$HCHO_{2}/NaCHO_{2}$ is an weak acid-conjugate base buffer. Hence, in accordance with Henderson-Hasselbalch equation-

$pH=pK_{a}(HCHO_{2})+log(\frac{[CHO_{2}^{-}]}{[HCHO_{2}]})$

Here, pH = 3.89, $pK_{a}$ of $HCHO_{2}$ = 3.74

So, $3.89=3.74+log(\frac{[CHO_{2}^{-}]}{[HCHO_{2}]})$

or, $\frac{[CHO_{2}^{-}]}{[HCHO_{2}]}$ = 1.41 (>1)

So, $[CHO_{2}^{-}]> [HCHO_{2}]$

or, $[NaCHO_{2}]> [HCHO_{2}]$

Hence, option (c) is correct.

6 0

4 years ago

Explain why the open ocean is often called a “marine desert”

s2008m [1.1K]

Answer:

Blue Open

Explanation:

Blue Planet - Open Ocean

Teachable Moments: The open ocean is often referred to as a "marine desert." ... However, the biodiversity in the open ocean, away from the flow of nutrients from the coasts, is the lowest for all aquatic ecosystems.

5 0

4 years ago