A car driving east along the freeway at 60 m/s hits some traffic and after 7 seconds is

Leya [2.2K]

Answer:

my probably best answer is B

5 0

3 years ago

a 5L container contains 3 moles of helium and 4 moles of hydrogen at a pressure of 9 atms maintaining a constant T and additiona

Stells [14]

Answer:

7.71 atm

Explanation:

Given the following data:

$V = 5 L$

$n_{He} = 3 mol$

$n_{H_2} = 4 mol$

$p_1 = 9 atm$

$T = const$

According to the ideal gas law, we know that the product between pressure and volume of a gas is equal to the product between moles, the ideal gas law constant and the absolute temperature:

$pV = nRT$

Since the temperature and the ideal gas constant are constants, as well as the fixed container volume of 5 L, we may rearrange the equation as:

$\frac{p}{n}=\frac{RT}{V}=const$

This means for two conditions, we'd obtain:

$\frac{p_1}{n_1}=\frac{p_2}{n_2}$

Given:

$p_1 = 9 atm$

$n_1 = n_{initial total} = n_{He} + n_{H_2} = 3 mol + 4 mol = 7 mol$

$n_2 = n_{final total} = n_{He} + n_{H_2} = 3 mol + 4 mol + 2 mol = 9 mol$

Solve for the final pressure:

$p_2 = p_1\cdot \frac{n_2}{n_1}$

Now, according to the Dalton's law of partial pressures, the partial pressure is equal to the total pressure multiplied by the mole fraction of a component:

$p_{H_2}=\chi_{H_2}p_2$

Knowing that:

$p_2 = p_1\cdot \frac{n_2}{n_1}$

And:

$\chi_{H_2}=\frac{n_H_2}{n_2}$

The equation becomes:

$p_{H_2}=\chi_{H_2}p_2=p_1\cdot \frac{n_2}{n_1}\cdot \frac{n_H_2}{n_2}=p_1\cdot \frac{n_H_2}{n_1}$

Substituting the variables:

$p_{H_2}=9 atm\cdot \frac{4 mol + 2 mol}{7 mol}=7.71 atm$

6 0

3 years ago

The empirical formula of styrene is CH; the molar mass of styrene is 104.14 g/mol. How many H atoms are present in a 7.80 g samp

Makovka662 [10]

Answer:

In 7.80 g of styrene, we have 3.60×10²³ atoms of H

Explanation:

Empirical formula of styrene is CH

Molecular formula of styrene is C₈H₈

So, 1 mol of styrene has 8 moles of C and 8 moles of H and 1 mol weighs 104.14 grams. Let's make a rule of three:

104.14 g (1 mol of C₈H₈) have 8 moles of H

Then 7.80 g would have ( 7.80 .8) / 104.14 = 0.599 moles

As we know, 1 mol of anything has NA particles (Avogadro's Number, 6.02×10²³), so 0.599 moles will have (mol . NA) particles

0.599 mol . 6.02×10²³ atoms / 1 mol = 3.60×10²³ atoms

3 0

3 years ago

Sulfur oxidation Choose one: A. contributes to global warming due to CO2 production. B. contributes to global warming due to met

iren2701 [21]

Answer:

C . causes environmental acidification due to production of sulfuric acid.

3 0

3 years ago

Calculate the density of chlorine gas in g/l, at stp.

vichka [17]

The Answer would be e: 3.2 g/L

<span>At STP : p = 1 atm and T = 273.15 K
molar mass Cl2 = 70.906 g/mol

d = molar mass x p/RT = 70.906 x 1 atm / 0.08206 x 273.15=3.16 g/L</span>

8 0

4 years ago