1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
ella [17]
3 years ago
8

Which of the following statements is most accurate?

Chemistry
1 answer:
Troyanec [42]3 years ago
4 0

Answer:

B

Explanation:

This is because exothermic reactions occurs when bnds are formed, and involves the release of energy.

Endothermic reaction occur when bonds are broken,and involves absorption of energy.

You might be interested in
ХА
kvasek [131]

Answer:

B. Biosphere.

Explanation:

8 0
3 years ago
Name a possible product of this reaction in the presence of ether and AlCl3: methylbenzene + 1-chlorodecane.a. 1-methyl-2-decylb
Vikki [24]

Answer:

None of these

Explanation:

Friedel–Craft reaction is a reaction involves the attachment of substituents to the benzene ring.

Mechanism of the reaction of methylbenzene with 1-chlorodecane in the presence of ether and aluminum chloride :

Step -1 : Generation of stable carbocation.

Aluminium chloride acts as Lewis acid which removes the chloride ion from the alkyl halide forming carbocation. The primary carbocation thus formed gets rearranged to secondary primary carbocation which is more stable due to hyperconjugation.

Step-2: Attack of the ring to the carbocation

The pi electrons of the ring behave as a nucleophile and attacks the carbocation. Since, the group attached on the benzene is methyl (+R effect) , the attack is from the ortho and the para positions. Para product is more stable due to less steric hinderance.

The product formed is shown in mechanism does not mention in any of the options.

So, None of these is the answer

8 0
4 years ago
Read 2 more answers
Ammonia can be determined spectrophotometrically by reaction with phenol in the presence of hypochlorite (OCl−):
Valentin [98]

Answer:

See explaination

Explanation:

Molar absorptivity, also known as the molar extinction coefficient, is a measure of how well a chemical species absorbs a given wavelength of light.

It is commonly used in chemistry and should not be confused with the extinction coefficient, which is used more often in physics.

Please kindly check attachment for the step by step solution of the given problem.

7 0
3 years ago
You have 500.0 ml of a buffer solution containing 0.30 m acetic acid (ch3cooh) and 0.20 m sodium acetate (ch3coona). what will t
Nataly [62]
First, we should get moles acetic acid = molarity * volume

                                                                =0.3 M * 0.5 L

                                                                =  0.15 mol

then, we should get moles acetate = molarity * volume

                                                           = 0.2 M * 0.5L

                                                           = 0.1 mol

then, we have to get moles of OH- which added:

moles OH- = molarity  * volume

                   = 1 M    * 0.02L

                  = 0.02 mol

when the reaction equation is:


                 CH3COOH  +  OH-  → CH3COO-   +  H2O


moles acetic acid after adding OH- = (0.15-0.02) 
                                             
                                                            =  0.13M                                       

moles acetate after adding OH- =  (0.1 + 0.02)

                                                      =   0.12 M

Total volume = 0.5 L + 0.02 L= 0.52 L

∴[acetic acid] = moles acetic acid after adding OH- / total volume

                        = 0.13mol / 0.52L

                       = 0.25 M

and [acetate ) = 0.12 mol / 0.52L
 
                        = 0.23 M

by using H-H equation we can get PH:

PH = Pka + ㏒[salt/acid]

when we have Ka = 1.8 x 10^-5

∴Pka = -㏒Ka 

        = -㏒ 1.8 x 10^-5

       = 4.7

So by substitution:

∴ PH = 4.7 + ㏒[acetate/acetic acid]

         = 4.7 + ㏒(0.23/0.25)

        = 4.66
6 0
3 years ago
Describe how platelets function
VashaNatasha [74]

Answer:

Platelets are tiny blood cells that help your body form clots to stop bleeding.

Explanation:

If one of your blood vessels gets damaged, it sends out signals to the platelets. The platelets then rush to the site of damage and form a plug (clot) to fix the damage.

7 0
3 years ago
Read 2 more answers
Other questions:
  • 5. Hurricane winds are strongest and rain is heaviest in the part of a hurricane called the<br>​
    9·2 answers
  • In the following reaction, 2NaCl 2Na + Cl2 sodium and chlorine are products, salts, reactants, or ions?
    12·2 answers
  • When iron metal reacts with sulfuric acid, it produces iron (III) sulfate and hydrogen gas. Balance the equation: Fe + H2SO4 → F
    11·1 answer
  • A package of aluminum foil is 63.2 yd long, 11 in. wide, and 0.00035 in. thick. If aluminum has a density of 2.70 g/cm³, what is
    5·1 answer
  • What s thisssss oneeeeeee
    9·1 answer
  • How can you tell S-wave arrival from the end of the P-wave?
    13·1 answer
  • The mass of the electron is..
    5·2 answers
  • Calculate the mass of iron oxide that contains a trillion iron atoms
    11·1 answer
  • A student pours ammonium nitrate into a container of room temperature water. The student stirs the mixture with a stirring rod a
    5·2 answers
  • A student dissolves 73 g of sodium nitrate, NaNO3, in 100 mL of water and observes a clear, colorless
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!