Molarity

Q.

Determine the percentage of oxygen in ammonium nitrate.

Q.

The volume-temperature relationship is given by _______ .

1. Dalton's Law

2. Gay Lussacs Law

3. Boyle's Law

4. Charle's Law

Q. Calculate the number of molecules of sulphur $\left(S_8\right)$ present in $16\text{g}$ of solid sulphur.
(Given, Atomic mass of sulphur $=32\text{u}$ and $N_A=6.022\times {10}^{23}$)

1. $4.022\times {10}^{15}\text{molecules}$
2. $6.022\times {10}^{22}\text{molecules}$
3. $3.76\times {10}^{22}\text{molecules}$
4. $3.76\times {10}^{30}\text{molecules}$

Q.

Select True or False:
Molarity of a solution depends upon temperature.

1. True

2. False

Q.

Solution of 100 ml water contains 0.73 g of Mg(HCO₃)₂ and 0.81 g of Ca(HCO₃)₂. Calculate the hardness in terms of ppm of CaCO₃.

1. 10² ppm

2. 10³ ppm

3. 10⁴ ppm

4. 5 × 10³ ppm

Q.

29.2% (w/W) HCl stock solution has a density of 1.25 g mL−1. The molecular weight of HCl is 36.5 mol−1. The volume (mL) of stock solution required to prepare a 200 mL solution 0.4 M HCl is:

1. $6ml$

2. $8ml$

3. $10ml$

4. $12ml$

Q. What is the concentration of nitrate ions if equal volumes of 0.1 M $AgN{O}_3$ and 0.1 M NaCl are mixed together

1. 0.1 M
2. 0.2 M
3. 0.05 M
4. 0.25 M

Q. How many moles and how many grams of NaCl are present in 250 mL of a 0.5 M NaCl solution?

1. 0.125 mol; 7.32 g
2. 7.32 mol; 0.125 g
3. 0.125 mol; 0.125 g
4. 7.32 mol; 7.32 g

Q. If $V$ ml of the vapours of substance at NTP weighs $W$ g. Then, molecular weight of substance is :

1. $\frac{W}{V}\times 22400$
2. $\frac{V}{W}\times 22.4$
3. $(W-V)\times 22400$
4. $\frac{W\times 1}{V\times 22400}$

Q. Calculate (i) the number of moles (ii) the number of molecules in 294 g of sulphuric acid.

Q. 3.6 grams of oxalic acid dissolve and volume is made upto 150 ml. Calculate the normatity of the solution for redox titration

1. $7.45$ N
2. $0.38$ N
3. $0.25$ N
4. $1.75$ N

Q. What is the number of aluminium ions present in 0.051 g of aluminium oxide $\left(A{l}_2{O}_3\right)$?

1. $3.011\times {10}^{20}$
2. $6.022\times {10}^{21}$
3. $6.022\times {10}^{20}$
4. $3.011\times {10}^{19}$

Q. A sample of ${Na}_2{CO}_3$ contains $6.02\times {10}^{23}{Na}^{+}ions$. The mass of the sample is: $(at.massofNa=23,C=12,O=16)$

Q.

This section contains 1 Assertion-Reason type question, which has 4 choices (a), (b), (c) and (d) out of which ONLY ONE is correct.

इस खण्ड में 1 कथन-कारण प्रकार का प्रश्न है, जिसमें 4 विकल्प (a), (b), (c) तथा (d) दिये गये हैं, जिनमें से केवल एक सही है।

A : At low pressure CO₂(g) shows more negative deviation than O₂(g).

A : निम्न दाब पर O₂(g) की अपेक्षा CO₂(g) अधिक ऋणात्मक विचलन दर्शाती है।

R : van der Waals constant ‘b’ for CO₂(g) is more than van der Waals constant ‘b’ of O₂(g).

R : O₂(g) के लिए वाण्डरवाल्स नियतांक ‘b’, की अपेक्षा CO₂(g) के लिए वाण्डरवाल्स नियतांक ‘b’ अधिक होता है।

1. Both (A) and (R) are true and (R) is the correct explanation of (A)
   
   (A) तथा (R) दोनों सही हैं तथा (R), (A) का सही स्पष्टीकरण है
2. Both (A) and (R) are true but (R) is not the correct explanation of (A)
   
   (A) तथा (R) दोनों सही हैं लेकिन (R), (A) का सही स्पष्टीकरण नहीं है
3. (A) is true but (R) is false
   
   A) सही है लेकिन (R) गलत है
4. (A) is false but (R) is true
   
   (A) गलत है लेकिन (R) सही ह

Q. The molarity of a solution obtained by mixing 750 mL of 0.5M HCl with 250 mL of 2M HCl will be:
(IIT-JEE-2013)

1. 1.75 M
2. 1.00 M
3. 0.975 M
4. 0.875 M

Q.

How many moles of sodium chloride are present in 250mL of a 0.50 M NaCI solution?

1. 0.125mol
2. 0.075mol
3. 0.150mol
4. 0.02mol

Q. What is the volume occupied by 4 grams of ethylene at $STP$ (in litres)?

1. 3.2
2. 22.4
3. 11.2
4. 5.6

Q. Calculate the percentage of iron in $K_{3}Fe(CN{)}_6$.

1. 17
2. 34
3. 15
4. 1.7

Q. 3.40 g of $CaS{O}_4(MW=136g/mol)$ is formed when 4.30 g of hydrated calcium sulphate heated to a constant mass. How many moles of water of crystallisation are combined with each mole of calcium sulphate?

1. 3
2. 2
3. 1
4. 4

Q. $Zn+2HCl⟶Zn{Cl}_2+H_2$
$H_2$ gas produced by the reaction is collected over water. If 0.3 g of Zn are consumed at ${27}^0$ in the reaction, calculate the volume of hydrogen produced. (Given: Barometric reading=750mm, Aqueous tension at $27$ =25 mm, Atomic weight of Zn=65.4).

Q. The percentage of $P_2{O}_5$ in diammonium hydrogen phosphate, $\left[\right(N{H}_4{)}_{2}HP{O}_4]$ is:

1. 23.48
2. 46.96
3. 71
4. 53.78

Q. How many gm of $H_2{SO}_4$ of density 1.84$/$ containing 95.6 mass % of $H_2{SO}_4$ should be added to 1 L of 40 mass % solution of $H_2{SO}_4$ of density 1.31$g/l$ in order to prepare 50 mass % solution of sulphuric acid of density 1.4 $g/l$

Q. How many ml of 1 (M) $H_{2}S{O}_4$ is required to neutralise 10 ml of 1 (M) NaOH solution

1. 2.5
2. 5
3. 10
4. 20

Q. If $6$g of $Fe$ reacts with $1$g of oxygen, the amount of $FeO$ formed will be $(Fe=56)$, if only FeO is formed as a product.

1. $4.5$g
2. $0.45$g
3. $6$g
4. $7.72$g

Q. The formula and molecular mass of caustic soda is :

1. $NaOH=40gmo{l}^{-1}$
2. $N{a}_{2}OH=63gmo{l}^{-1}$
3. $Na(OH{)}_2=57gmo{l}^{-1}$
4. none of the above

Q.

Which of the following are molecules of compounds?
(I) Carbon dioxide
(II) Chlorine gas
(III) Hydrogen Chloride

1. All I, II and III

2. Both I and III

3. Only II

4. Only I

Q. When $0.100$ mole of ammonia, ${NH}_3$, is dissolved in sufficient water to make $1.0L$ of solution, the solution is found to have a hydroxide ion concentration of $1.34\times {10}^{-3}M$. Calculate $K_b$ for ammonia.

Q. What volume of a liquid will contain 4 moles?
Molar mass of liquid is 280 and its density is $1.4g/mL$

1. $0.4L$
2. $1.6L$
3. $4.8\times {10}^{23}L$
4. $0.8L$

Q.

The mole fraction of solvent in a solution having 6 moles of sugar dissolved in 18 moles of solvent is

1. 0.50

2. 0.25

3. 0.75

4. 1.00

Q. 29.2% (w/W) HCl stock solution has density of $1.25gm{L}^{-1}.$ The molecular weight of HCl is 36.5 g $mo{l}^{-1}.$The volume (mL) of stock ___