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2 years ago

What has caused air quality in United States to improve/get better since the 1950s?

Chemistry

2 answers:

weeeeeb [17]2 years ago

8 0

Answer:

better mileage on cars, took lead out of paint, smaller packaging like for delivery and store products, EPA laws updating

stealth61 [152]2 years ago

8 0

Answer:

Reducing pollution from transportation sources has led to healthier air for Americans. In cities, smog has been visibly reduced.

Explanation:

i hope this helped

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How many molecules are in 41.8 g of sulfuric acid

Anton [14]

Answer

× 10²³ molecules are in 41.8 g of sulfuric acid

Explanation

The first step is to convert 41.8 g of sulfuric acid to moles by dividing the mass of sulfuric acid by its molar mass.

Molar mass of sulfuric acid, H₂SO₄ = 98.079 g/mol

$Mole=\frac{Mass}{Molar\text{ }mass}=\frac{41.8\text{ }g}{98.079\text{ }g\text{/}mol}=0.426187053\text{ }mol$

Finally, convert the moles of sulfuric acid to molecules using Avogadro's number.

Conversion factor: 1 mole of any substance = 6.022 × 10²³ molecules.

Therefore, 0.426187053 moles of sulfuric acid is equal

$\frac{0.426187053\text{ }mol}{1\text{ }mol}\times6.022×10²³\text{ }molecules=2.57\times10^{23}\text{ }molecules$

Thus, 2.57 × 10²³ molecules are in 41.8 g of sulfuric acid.

3 0

8 months 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: Ni^2+ (aq) + S^2- (aq) ----> + Ni (s) + S (s)

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

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: Pb^2+ (aq) +H2 (g) ----> Pb (s) +2H^+ (aq)

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: 2Ag^+ (aq) + Cr(s) ---> 2 Ag (s) +Cr^2+ (aq)

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

Water vapor is not usually seen.

xeze [42]

Answer:

True

Explanation:

Water vapor is totally invisible.

Without it, there would be no clouds or rain or snow, since all of these require water vapor in order to form. All of the water vapor that evaporates from the surface of the Earth eventually returns as precipitation - rain or snow.

Helped by the One & Only #QUEEN aka #DRIPPQUEENMO

Hoped this helped! :)

5 0

2 years ago

6. if a cross country runner travels at a speed of 10 mph and he runs for 2 hours, how many miles will he have run at the end of

storchak [24]

Explanation:

distance = speed x time

distance = 10 x 2

distance = 20miles

hope that helps :)

5 0

2 years ago

Give the formula of each of the following (don't worry about subscripts or superscripts, example: HCO3- enter as HCO3-): the con

vovangra [49]

Answer:

The relative conjugate acids and bases are listed below:

CH3NH2 → CH3NH3+

H2SO3→ HSO3-

NH3→ NH4+

Explanation:

In a Brønsted-Lowry acid-base reaction, a conjugate acid is the species resulting from a base accepting a proton; likewise, a conjugate base is the species formed after an acid has donated a hydrogen atom (proton).

To this end:

HSO3- is the conjugate acid of H2SO3 i.e sulfuric acid has lost a proton (H+)
NH4+ is the conjugate acid of NH3 i.e the base ammonia has gained a proton (H+)
OH- is the conjugate base of H20
CH3NH3+ is the conjugate base of the base CH3NH2 methylamine

3 0

2 years ago

Read 2 more answers

What has caused air quality in United States to improve/get better since the 1950s?￼

What has caused air quality in United States to improve/get better since the 1950s?