Which of the following shows a decrease in entropy?

The rate of effusion of an unknown gas was measured and found to be 11.9 mL/min. Under identical conditions, the rate of effusio

iren2701 [21]

Answer : The correct option is, (B) $CO_2$

Solution :

According to the Graham's law, the rate of effusion of gas is inversely proportional to the square root of the molar mass of gas.

$R\propto \sqrt{\frac{1}{M}}$

or,

$(\frac{R_1}{R_2})=\sqrt{\frac{M_2}{M_1}}$ ..........(1)

where,

$R_1$ = rate of effusion of unknown gas = $11.9\text{ mL }min^{-1}$

$R_2$ = rate of effusion of oxygen gas = $14.0\text{ mL }min^{-1}$

$M_1$ = molar mass of unknown gas = ?

$M_2$ = molar mass of oxygen gas = 32 g/mole

Now put all the given values in the above formula 1, we get:

$(\frac{11.9\text{ mL }min^{-1}}{14.0\text{ mL }min^{-1}})=\sqrt{\frac{32g/mole}{M_1}}$

$M_1=44.2g/mole$

The unknown gas could be carbon dioxide $(CO_2)$ that has approximately 44 g/mole of molar mass.

Thus, the unknown gas could be carbon dioxide $(CO_2)$

5 0

3 years ago

What is the maximum kinetic energy of an ejected electron if silver metal is irradiated with 224 nm light? The

Genrish500 [490]

Answer:The maximum kinetic energy KEe of ejected electrons (photoelectrons) is given by KEe=hf−BE KE e = h f − BE , where hf is the photon energy and BE is the binding energy (or work function) of the electron to the particular material.

Explanation:

3 0

3 years ago

2zn+o2=2zno <br><br> how many moles of zinc are needed to make 6 moles of zinc oxide?

Temka [501]

Answer:

$\boxed{\text{6 mol}}$

Explanation:

(a) Balanced equation

2Zn + O₂ ⟶ 2ZnO

(b). Calculation

You want to convert moles of ZnO to moles of Zn

The molar ratio is 2 mol Zn:2 mol ZnO

$\text{Moles of Zn} =\text{6 mol ZnO} \times \dfrac{\text{2 mol Zn}}{\text{2 mol ZnO}} = \text{6 mol Zn}\\\\\text{You need }\boxed{\textbf{6 mol of Zn}}\text{ to form 6 mol of ZnO}.$

3 0

3 years ago

What two categories are used in classifying particulate matter?

Allushta [10]

<span>The two categories for classifying particulate matter are through analysis of the intensive and extensive properties. Intensive properties are independent properties that can be measured independent of the amount of matter while extensive properties are measured dependent on the amount.</span>

3 0

3 years ago

The combustion of Ibuprofen C13H18O2 produces water and carbon

prohojiy [21]

Answer:

277.7 g of CO2

Explanation:

Equation of reaction

C13H18O2 + 11O2 ---> 13CO2 + 9H2O

From the equation of reaction

1 mole of ibuprofen produces 13 moles of CO2

Molar mass of ibuprofen is 206g

Molar mass of CO2 is 44g

13 moles of CO2 weighs 572g

Therefore, 100g of ibuprofen will produce (100×572)/206 of CO2

= 277.7g

6 0

3 years ago