Gas laws and mole concept - class-X

Question 1 Multiple Choice (Single Answer)

A quantity of $2.0\ g$ of a triatomic gaseous element was found to occupy a volume of $448\ ml$ at $76\ cm$ of $Hg$ and $273\ K$.

The mass of its each atom is _______________.

$100\ amu$
$5.53\times 10^{-23}\ g$
$33.3\ g$
$5.53\ amu$

Question 2 Multiple Choice (Single Answer)

Which of the following gas molecule has the longest mean free path at the same pressure and temperature?

$H _2$
$N _2$
$O _2$
$Cl _2$

Question 3 Multiple Choice (Single Answer)

Two gases X and Y have their molecular speed in ratio of $3:1$ at certain temperature. The ratio of their molecular masses $M _x:M _y$ is?

$1:3$
$3:1$
$1:9$
$9:1$

Question 4 Multiple Choice (Single Answer)

The waste of nuclear power plant contains $C^{12}$ and $C^{14}$ in ratio of $4:1$ by moles. What is the molecular mass of methane gas produced from this disposed of $C^{12}$ and $C^{14}$ are $98%$ and $2%$, respectively.

$15.998$
$16.0053$
$16$
$16.4$

Question 5 Multiple Choice (Single Answer)

A gaseous mixture of three gases A, B and C has a pressure of $10$ atm. The total number of moles of all the gases is $10$. If the partial pressures of A and B are $3.0$ and $1.0$ atm, respectively, and if C has molecular mass of $2.0$, what is the mass of C, in g, present in the mixture?

$6$
$8$
$12$
$3$

Question 6 Multiple Choice (Single Answer)

A quantity of $5.0$g of a mixture of He and another gas occupies a volume of $1.5$l at $300$K and $750$mm Hg. The gas freezes at $270$K. At $15$K, the pressure of the gas mixture is $8$mm Hg(at the same volume). What is the molecular mass of the gas?

$103.8$
$4.0$
$495$
$82.24$

Question 7 Multiple Choice (Single Answer)

1 mole of a compound contains 1 mole of C and 2 moles of O. The molecular weight of the compound is:

3
12
32
44

Question 8 Multiple Choice (Single Answer)

What is the weight of $3$ gram atoms of sulphur?

$96 g$
$99 g$
$100 g$
$3 g$

Question 9 Multiple Choice (Single Answer)

Iron pyrites has formula $FeS _2. (Fe = 56; S = 32)$. What is the mass of sulfur contained in 30 grams of pyrites?

16 g
32 g
20 g
24 g

Question 10 Multiple Choice (Single Answer)

The mass of one molecule of water is approximately:

$1\ g$
$0.5\ g$
$1.66 \times 10^{-24}\, g $
$ 3 \times 10^{-23}\, g $

Question 11 Multiple Choice (Multiple Answers)

In an experiment, the following four gases were produced. 11.2 L of which two gases at STP will weigh 14 g ?

$N _2O$
$NO _2$
$N _2$
$CO$

Question 12 Multiple Choice (Single Answer)

If of conservation of mass was to hold true, then 20.8 g of ${ BaCl } _{ 2 }$ on reaction with 9.8 g of ${ H } _{ 2 }{ SO } _{ 4 }$ will produce 7.3 g of $HCl$ and ${ BaSO } _{ 4 }$ equal to :

11.65 g
23.3 g
25.5 g
30.6 g

Question 13 Multiple Choice (Single Answer)

A gaseous alkane is exploded with oxygen. The volume of ${O} _{2}$ for complete combustion of alkane to $C{O} _{2}$ formed is in the ratio $7:4$. The molecular formula of alkane is:

${C} _{2}{H} _{6}$
${C} _{3}{H} _{8}$
${C} _{4}{H} _{10}$
$C{H} _{4}$

Gas laws and mole concept - class-X

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