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
valentina_108 [34]
3 years ago
12

Many biochemical processes are described as coupled reactions. which of the following statements are true? 1 the first step is e

ndergonic. 2 a second reaction is required to make the first spontaneous. 3 the second step is not spontaneous. 4 the net dg for the two reactions is negative.
Chemistry
1 answer:
Romashka-Z-Leto [24]3 years ago
6 0
90 feet from home plate to the second base
You might be interested in
Which of the compounds above are strong enough acids to react almost completely with a hydroxide ion (pka of h2o = 15.74) or wit
luda_lava [24]

The compounds can react with OH⁻ and HCO₃⁻ only C₅H₆N pyridinium

<h3><em>Further explanation </em></h3>

In an acid-base reaction, it can be determined whether or not a reaction occurs by knowing the value of pKa or Ka from acid and conjugate acid (acid from the reaction)

Acids and bases according to Bronsted-Lowry

Acid = donor (donor) proton (H + ion)

Base = proton (receiver) acceptor (H + ion)

If the acid gives (H +), then the remaining acid is a conjugate base because it accepts protons. Conversely, if a base receives (H +), then the base formed can release protons and is called the conjugate acid from the original base.

From this, it can be seen whether the acid in the product can give its proton to a base (or acid which has a lower Ka value) so that the reaction can go to the right to produce the product.

The step that needs to be done is to know the pKa value of the two acids (one on the left side and one on the right side of the arrow), then just determine the value of the equilibrium constant

Can be formulated:

K acid-base reaction = Ka acid on the left : K acid on the right.

or:

pK = acid pKa on the left - pKa acid on the right

K = equilibrium constant for acid-base reactions

pK = -log K;

K~=~10^{-pK}

K value> 1 indicates the reaction can take place, or the position of equilibrium to the right.

There is some data that we need to complete from the problem above, which is the pKa value of some compounds that will react, namely:

pyridinium pKa = 5.25

acetone pKa = 19.3

butan-2-one pKa = 19

Let's look at the K value of each possible reaction:

pka H₂O = 15.74, pka of H₂CO₃ = 6.37)

  • 1. C₅H₆N pyridinium

* with OH⁻

C₅H₆N + OH- ---> C₅H₅N- + H₂O

pK = pKa pyridinium - pKa H₂O

pK = 5.25 - 15.74

pK = -10.49

K~=~10^{4.9}

K values> 1 indicate the reaction can take place

* with HCO3⁻

C₅H₆N + HCO₃⁻-- ---> C₅H₅N⁻ + H₂CO₃

pK = 5.25 - 6.37

pK = -1.12

K`=~10^{1.12]

Reaction can take place

  • 2. Acetone C₃H₆O

* with OH-

C₃H₆O + OH⁻ ---> C₃H₅O- + H₂O

pK = 19.3 - 15.74

pK = 3.56

K~=~10^{ -3.56}

Reaction does not happen

* with HCO₃-

C₃H₆O + HCO₃⁻ ----> C₃H₅O⁻ + H₂CO₃

pK = 19.3 - 6.37

pK = 12.93

K`=~10 ^{-12.93}

Reaction does not happen

  • 3. butan-2-one C₄H₇O

* with OH-

C₄H₇O + OH- ---> C₄H₆O- + H₂O

pK = 19 - 15.74

pK = 3.26

K~=~10^{-3.26}

Reaction does not happen

* with HCO₃⁻

C₄H₇O + HCO₃⁻ ---> C₄H₆O⁻ + H₂CO₃

pK = 19 - 6.37

pK = 12.63

K~=~ 10^{-12.63}

Reaction does not happen

So that can react with OH⁻ and HCO₃⁻ only C₅H₆N pyridinium

<h3><em>Learn more </em></h3>

the lowest ph

brainly.com/question/9875355

the concentrations at equilibrium.

brainly.com/question/8918040

the ph of a solution

brainly.com/question/9560687

Keywords : acid base reaction, the equilibrium constant

5 0
3 years ago
Read 2 more answers
Which of the following is an example of a change of state?
lord [1]

Answer:

Option B

Explanation:

  • For Option A the state is not changing but just has different look now.
  • For Option B the state is changing from gas to liquid drops due to cold glass
  • For Option C it hasn't changed state as both corn and flower is solid
  • For Option D paper and ash are both solids

Therefore our answer must be Option B

6 0
2 years ago
HELP ASAS 15 POINTS
kramer

Answer:

liquid will be evaporated while solid remains

3 0
2 years ago
Iron has a density of 7.87 g/cm3. What is the volume in cm3 of 3.729 g of iron?
KIM [24]

If iron has a density of 7.87g/cm³ and a mass of 3.729g, then the volume of iron is 0.474cm³

HOW TO CALCULATE VOLUME:

  • The volume of a substance can be calculated by dividing the mass by its density. That is;

Volume (mL) = mass (g) ÷ density (g/mL)

  • The density of iron is given as 7.87g/cm³ while its mass is 3.729g of iron. Hence, the volume can be calculated as follows:

Volume = 3.729 ÷ 7.87

Volume = 0.474cm³

Therefore, the volume of iron is 0.474cm³

Learn more: brainly.com/question/2040396?referrer=searchResults

6 0
2 years ago
Match each of the following forms of sugar to its best description?
prohojiy [21]

Sucrose, a sweet, white crystalline substance, C12 H22 O11, OBTAINED CHIEFLY FROM THE JUICE OF THE SUGAR CANE AND SUGAR BEET, BUT ALSO PRESENT IN SORGHUM, THE sugar maple, some palms, and various other plants, and having extensive nutritional, pharmaceutical, and industrial uses; any of the class of carbohydrates to which this substance belongs, as glucose,  levulose, and lactose.
5 0
3 years ago
Other questions:
  • How does energy transform during solar power process
    5·1 answer
  • A(g) + b(g) =&gt; ab(g), the rate is 0.239 mol/l.s when the initial concentrations of both a and b are 2.00 mol/l. if the reacti
    12·1 answer
  • The ancient remains or trace of once-living things.
    12·1 answer
  • Which statement best describes a possible way that
    14·1 answer
  • A 63.5 g sample of an unidentified metal absorbs 355 ) of heat when its temperature changes
    6·1 answer
  • Please help with this
    10·2 answers
  • In a particular genetic cross, the probability of the offspring having a certain trait is Which percentage represents this proba
    6·1 answer
  • What is the Empirical Formula when the Molecular Formula is Sb17Br21
    9·1 answer
  • if you are given one element name and % by mass, how do you find the other element in the compound? give example plz
    9·1 answer
  • The total number of electron pairs in a nitrogen molecules.is:<br> a) 2<br> b) 3<br> c) 5<br> d) 7​
    12·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!