DDT was banned from use as a pesticide in the United States because

Reptile [31]

<span>The answer is B.They cannot produce enough heat to keep their bodies warm.

In order to survive, the alligators rely on warm weather, and they are most active when the environment is 82-92 degrees Fahrenheit. They can survive below or above this temperature range but they may spend that time struggling to stay warm or stay cool.

</span>

5 0

3 years ago

Based on the sign of E cell, classify these reactions as spontaneous or non spontaneous as written.? assume standard conditions.

sammy [17]

A electrochemical reaction is said to be spontaneous, if $E^{0} cell is positive.$

Answer 1:
Consider reaction: <span>Ni^2+ (aq) + S^2- (aq) ----> + Ni (s) + S (s)

The cell representation of above reaction is given by;
  </span> $S^{2-}/S // Ni^{2+}/Ni$

Hence, $E^{0}cell = E^{0} Ni^{2+/Ni} - E^{0} S/S^{2-}$
we know that, ${E^{0} Ni^{2+}/Ni = -0.25 v$
and ${E^{0} S/ S^{2-} = -0.47 v$

Therefore, $E^{0} cell$ = - 0.25 - (-0.47) = 0.22 v

Since, $E^{0} cell$ is positive, hence cell reaction is spontaneous
.....................................................................................................................

Answer 2:
Consider reaction: <span>Pb^2+ (aq) +H2 (g) ----> Pb (s) +2H^+ (aq)
</span>
The cell representation of above reaction is given by;
   $H_{2} / H^{+} // Pb^{2+} /Pb$

Hence, $E^{0}cell = E^{0} Pb/Pb^{2+} - E^{0} H_{2}/H^{+}$
we know that, ${E^{0} Pb^{2+}/Pb = -0.126 v$
and ${E^{0} H_{2}/ H^{+} = -0 v$

Therefore, $E^{0} cell$ = - 0.126 - 0 = -0.126 v

Since,   $E^{0} cell$ is negative, hence cell reaction is non-spontaneous.

....................................................................................................................

Answer 3:
Consider reaction: <span>2Ag^+ (aq) + Cr(s) ---> 2 Ag (s) +Cr^2+ (aq)
</span>
The cell representation of above reaction is given by;
   $Cr/Cr^{2+} // Ag^{+}/Ag$

Hence, $E^{0}cell = E^{0} Ag^{+}/Ag - E^{0} Cr/Cr^{2+}$
we know that, ${E^{0} Ag^{+}/Ag = -0.22 v$
and ${E^{0} Cr/ Cr^{2+} = -0.913 v$

Therefore, $E^{0} cell$ = - 0.22 - (-0.913) = 0.693 v

Since,   $E^{0} cell$ is positive, hence cell reaction is spontaneous

8 0

3 years ago

Read 2 more answers

What are the different redox states of nitrogen in the ocean and what are example chemical species? Please give at least three.

enot [183]

Nitrogen exists in the ocean in three redox states:

In + 3 state as ammonium ion, NH4+
In the 0 state as nitrogen gas
In the +5 state as trioxonitrate (v) ion, NO3-

<h3>What are redox states?</h3>

The redox state of an element is the charge it appears to have in the free or combined state.

Nitrogen exists in the ocean in three redox states:

In + 3 state as ammonium ion, NH4+
In the 0 state as nitrogen gas
In the +5 state as trioxonitrate (v) ion, NO3-

Therefore, the redox state of nitrogen varies in the ocean.

Learn more about redox state at: brainly.com/question/26263317

3 0

2 years ago

What happens after condensation to cause precipitation?

babymother [125]

Answer:

The answer is c, Clouds fill with moisture and get too hravy

6 0

3 years ago

The highest amount of oxygen will be found in soils containing large amounts of _____. The highest amount of oxygen will be foun

ANEK [815]

Answer:

Gravel. It has high proportion of oxygen

4 0

3 years ago