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3 years ago

Why is acetic anhydride added slowly to a dichloromethane solution of the other reactants?

2 answers:

8 0

Acetic anhydride is the only monocarboxylic acid anhydride which is an acylating agent capable of modifying reactions. The dichloromethane is the reaction solvent.

The acetic anhydride should be added slowly through a separatory funnel to other reactants so as to avoid a runaway reaction, also known as thermal runaway. By doing this the reaction mixture boils as gently as possible while stirring. This phenomenon occurs in situations where an increase in temperature changes the conditions in a way that leads to destructive result brought about by a further increase in temperature.

creativ13 [48]3 years ago

8 0

Acetic Acid is considered one of the excellent source of Acyl (CH₃CO-) group. It is also one of the the most reactive derivative of Carbonyl groups.

As we know that the bond formation is an Exothermic reaction. Greater the rate of formation of new bonds greater will be the amount of heat released.

Hence, Acetic Anhydride being more reactive will produce more heat on reaction with other reactants and generates more heat. In order to prevent the reaction mixture from bursting the reaction is often carried out at lower temperatures and also the rate of addition of Acetic Anhydride is slowed down.

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HELP PLEASE (Solve this problem using the appropriate law). what is the volume of 0.382 moles of hydrogen gas at 1.50 atmosphere

kaheart [24]

Answer:

V = 6.17 L

Explanation:

Given data:

Volume = ?

Number of moles = 0.382 mol

Pressure = 1.50 atm

Temperature = 295 k

R = 0.0821 L. atm. /mol. k

Solution:

According to ideal gas equation:

PV= nRT

V = nRT/P

V = 0.382 mol × 0.0821 L. atm. /mol. k ×295 k / 1.50 atm

V = 9.252 L. atm. / 1.50 atm

V = 6.17 L

5 0

3 years ago

Why does nuclear fusion occur in stars but not on Earth?

disa [49]

Answer:

Fusion reactions require a lot of heat and pressure

Explanation:

nuclear fusion takes place only at extremely high temperatures. That's because a great deal of energy is needed to overcome the force of repulsion between the positively charged nuclei. ... A: Nuclear fusion doesn't occur naturally on Earth because it requires temperatures far higher than Earth temperatures.

4 0

3 years ago

Read 2 more answers

How many grams of Cl are in a 38.0-g sample of the chlorofluorocarbon CF2Cl2

Katena32 [7]

The molecular formula of chlorofluorocarbon is CF₂Cl₂
Molecular mass of CF₂Cl₂ is 120.9 g/mol
Mass of Cl in 1 mol - 2 x 35.5 = 71 g/mol
in 120.9 g of compound - 71 g of Cl
Therefore in 38 g of sample - 71/120.9 x 38 g of Cl
Mass of Cl in 38 g - 22.31 g of Cl

4 0

3 years ago

Define organic evolution.

vazorg [7]

Answer:

Organic evolution is the theory that more recent types of plants and animals have their origins in other pre-existing forms and that the distinguishable differences between ancestors and descendents are due to modifications in successive generations.

Explanation:

5 0

2 years ago

Be sure to answer all parts. Sulfur dioxide is released in the combustion of coal. Scrubbers use lime slurries of calcium hydrox

scoray [572]

<u>Answer:</u> The balanced chemical equation is written below and $\Delta S^o$ for the reaction is -160.6 J/K

<u>Explanation:</u>

When calcium hydroxide reacts with sulfur dioxide, it leads to the formation of calcium sulfate and water molecule.

The chemical equation for the reaction of calcium hydroxide and sulfur dioxide follows:

$Ca(OH)_2(s)+SO_2(g)\rightarrow CaSO_3(s)+H_2O(l)$

To calculate the entropy change of the reaction, we use the equation:

$\Delta S^o_{rxn}=\sum [n\times \Delta S^o_{products}]-\sum [n\times \Delta S^o_{reactants}]$

For the given reaction:

$\Delta S^o_{rxn}=[(1\times \Delta S^o_{CaSO_3(s)})+(1\times \Delta S^o_{H_2O(l)})]-[(1\times \Delta S^o_{Ca(OH)_2(s)})+(1\times \Delta S^o_{SO_2(g)})]$

Taking the standard entropy change values:

$\Delta S^o_{CaSO_3(s)}=101.4Jmol^{-1}K^{-1}\\\Delta S^o_{H_2O(l)}=69.9Jmol^{-1}K^{-1}\\\Delta S^o_{Ca(OH)_2(s)}=83.4Jmol^{-1}K^{-1}\\\Delta S^o_{SO_2(g)}=248.5Jmol^{-1}K^{-1}$

Putting values in above equation, we get:

$\Delta S^o_{rxn}=[(1\times (101.4))+(1\times (69.9))]-[(1\times (83.4))+(1\times (248.5))]\\\\\Delta S^o_{rxn}=-160.6J/K$

Hence, the balanced chemical equation is written above and $\Delta S^o$ for the reaction is -160.6 J/K

3 0

2 years ago