2. Which statement is false about the atoms of a given element?

What purpose do each of the following play in the isolation and purification of ethyl 3- hydroxybutanoate?

Shalnov [3]

Explanation:

-Filter help — delete some big unreacted, undesirable species (norit is probably from what you are sorting through, its only carbon which cleans up things)

— extract with DCM because you are probably in an aqueous phase, and some butanoate is in it

- Anhydrous sodium absorbs excess of water (dries the material)

-evaporation in the hood to clear the DCM and crystallize the product.

8 0

3 years ago

An arctic weather balloon is filled with 27.8 L of helium gas inside a prep shed. The temperature inside the shed is . The ballo

Liula [17]

The question is incomplete, here is a complete question.

An arctic weather balloon is filled with 27.8 L of helium gas inside a prep shed. The temperature inside the shed is 13 ⁰C. The balloon is then taken outside, where the temperature is -9 ⁰C. Calculate the new volume of the balloon. You may assume the pressure on the balloon stays constant at exactly 1 atm. Be sure your answer has the correct number of significant digits.

Answer : The new volume of the balloon is 25.7 L

Explanation :

Charles's Law : It is defined as the volume of the gas is directly proportional to the temperature of the gas at constant pressure and number of moles.

$V\propto T$

or,

$\frac{V_1}{T_1}=\frac{V_2}{T_2}$

where,

$V_1$ = initial volume of gas = 27.8 L

$V_2$ = final volume of gas = ?

$T_1$ = initial temperature of gas = $13^oC=273+13=286K$

$T_2$ = final temperature of gas = $-9^oC=273+(-9)=264K$

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

$\frac{27.8L}{286K}=\frac{V_2}{264K}$

$V_2=25.7L$

Therefore, the new volume of the balloon is 25.7 L

3 0

2 years ago

The mass of an electron is approximately equal to 1 over 1,836 of the mass of 1. a positron 2. a proton 3. an atom of helium 4.

lianna [129]

Hello!

It would be A, the proton.

5 0

3 years ago

Read 2 more answers

11C. Potassium hydrogen phthalate is a solid, monoprotic acid frequently used in the laboratory to standardize strong base solut

Llana [10]

For the reactants,

The oxidation number of hydrogen = +1
The oxidation number of oxygen = -2
The oxidation number of arsenic = +5
The oxidation number of carbon = +3

For the products,

The oxidation number of hydrogen = +1
The oxidation number of oxygen = -2
The oxidation number of arsenic = +3
The oxidation number of carbon = +4

Here, arsenic (+5 to +3) and carbon (+3 to +4) are the only oxidation numbers changing.

Note that an increase in oxidation number means electrons are lost. Thus oxidation is occurring, and a decrease in oxidation number means electrons are being gained, and thus reduction is occurring.

Also, the compound that contains the element being oxidized is the reducing agent, and the compound that contains the element being reduced is the oxidizing agent.

So, the answers are:

name of the element oxidized: Carbon

name of the element reduced: Arsenic

formula of the oxidizing agent: $\text{H}_{3}\text{AsO}_{4}$

formula of the reducing agent: $\text{H}_{2}\text{C}_{2}\text{O}_{4}$

6 0

1 year ago

Pure R,R-hydrobenzoin (side product of meso-hydrobenzoin) has a melting point of 148°C. a) What do you expect the melting point

Alexandra [31]

Answer:

Explanation:

(a) melting point of S,S-hydrobenzoin should be 140°C. Since S,S-hydrobezoin and R,R-hydrobenzoin are enantiomeric pair so that their melting point and boilong point should be same.

(b) different melting point,

Racemic mixture must have different melting point in comparison to the pure enantiomers.

considering a racemic mixture, individual enantiometer possesses a greater affinity for its kind of molecules than for those of the other enantiometer

3 0

3 years ago