Avogadro's Law

Q.

Write the relation between molecular mass and vapour density.

Q.

(a) What are the main applications of Avogadro's law?
(b) How does Avogadro's law explain Gay-Lussac's law of combining volumes?

Q.

How many carbon atoms are present in 0.35 mol of $C_6{H}_{12}{O}_6$ :

1. carbon atoms
2. carbon atoms
3. carbon atoms
4. carbon atoms

Q.

Calculate the percentage of water of crystallization in a sample of washing soda, ${\mathrm{Na}}_2{\mathrm{CO}}_3.10{\mathrm{H}}_2\mathrm{O}$. $\left[\mathrm{Na}=23,\mathrm{C}=12,\mathrm{O}=16,\mathrm{H}=1\right]$

Q.

The reaction between aluminium carbide and water takes place according to the following equation:
$A{l}_4{C}_3+12H_{2}O\to 3C{H}_4+4Al(OH{)}_3$
Calculate the volume fo methane measured at STP released from 14.4 g of aluminum carbide by excess fo water.

Q.

How many atoms does one mole of Phosphorus contain?

Q.

The number of carbon atoms present in a signature, if a signature written by carbon pencil weighs $1.2\times {10}^{-3}$ g is:

1. 
   
2. 
3. 
4. 
   

Q.

Concentrated nitric acid oxidises phosphorus to phosphoric acid according to the following equation:
$P+5HN{O}_3\to H_{3}P{O}_4+5N{O}_2+H_{2}O$
If 6.2 g of phosphorus was used in the reaction, calculate:

(a) The number of moles of phosphorus taken and mass of phosphoric acid formed.
(b) Mass of nitric acid consumed at the same time.
(c) The volume of steam produced at the same time if measured at 760 mm Hg pressure and ${273}^{\circ }C.$

Q.

(a)What is the main application of Avogadro's Law?
(b) How does Avogadro's Law explain Gay-Lussac's law of combining volume?

Q.

According to which law equal volumes of all gases, at the same temperature and pressure, have the same number of molecules.

1. Charles Law
2. Boyles Law
3. Avogadro's law
4. Gay Lussac's Law

Q.

If two gases under constant temperature and pressure have the same number of molecules then they must have different volumes.

1. True

2. False

Q.

Maximum number of electrons is present in $O_2$

1. 2 mole atoms of of sulphur

2. 2.24 lit. of SO2 at S.T.P

3. 0.2 moles of NH3

4. 1.5 gm moles of oxygen

Q.

1.8 g of oxalic acid ( H₂C₂O₄) is dissolved in 200 mL of a solution. Find out the molarity of the resultant solution.

Q.

How many times hydrogen is lighter than air?

Q.

Calcium carbonate reacts with nitric acid to give salt, gas X and water. What is X?

1. CO₂

2. O₂

3. SO₂

4. NO₂

Q.

Calculate the percentage composition of hydrogen in ${\mathrm{C}}_6{\mathrm{H}}_{12}{\mathrm{O}}_6\left[\mathrm{C}=12,\mathrm{H}=1,\mathrm{O}=16\right]$.

Q.

Calculate the volume occupied by 0.8 g of methane at STP.

Q.

The number of carbon atoms present in a signature, if a signature written by carbon pencil weights $1.2\times {10}^{-3}$ g is:

1. $12.04\times {10}^{20}$

2. $6.02\times {10}^{19}$

3. $3.01\times {10}^{19}$

4. $6.02\times {10}^{20}$

Q.

$BaC{l}_{\mathit{2}}.n{\mathrm{H}}_2\mathrm{O}$ Barium chlorides crystals contain $14.8\%$ water of crystallization per molecule of barium chloride.

Q.

Explain the term ‘mole’ and Avogadros number. How are they related?

Q. How many moles are present in one 1 atom of carbon?

1. $1.0$
2. $0.50$
3. $0.166\times {10}^{-23}$
4. $6.023\times {10}^{23}$

Q.

1 mole contains ____ atoms, molecules, or ions of a substance.

Q.

Calculate the percentage composition of chromium in potassium dichromate, ${\mathrm{K}}_2{\mathrm{Cr}}_2{\mathrm{O}}_7$.

$\left[\mathrm{K}=39,\mathrm{Cr}=52,\mathrm{O}=16\right]$

Q.

You have collected (a) 2 litres of $C{O}_2$ (b) 3 litres fo chlorine (c) 5 litres fo hydrogen (d) 4 litres of nitrogen and (e) 1 litre fo $S{O}_2$ under similar conditions of temperature and pressure. Which gas sample will have:
(a) the greatest number of molecules, and
(b) the least number of molecules?
justify your answers.

Q.

The volume of a gas at a given temperature and pressure is proportional to the number of particles.

1. False

2. True

Q.

According to the Avogadro’s law, what is the molar volume of gases at STP?

1. 224 L

2. 22.4 cm³

3. 22.4 ml³

4. 22.4 L

Q.

Which of the following statement regarding Avogadro's law is incorrect?

1. Pressure is constant.

2. Temperature is constant.

3. Volume is constant.

4. Volume is directly proportional to the number of molecules.

Q.

Maximum number of electrons is present in

1. 0.2 moles of NH3

2. 2 mole atoms of of sulphur

3. 1.5 gm moles of oxygen

4. 2.24 lit. of SO2 at S.T.P

Q. Avogadro's law determines ___ and the molecular formula of the gas.

1. atomicity
2. electronegativity
3. electropositivity
4. atomic mass

Q.

Find the weight of $0.2\text{moles}$ of ${\text{H}}_2$ gas.