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Carbohydrates: carbon, hydrogen, oxygen

Protein: carbon, hydrogen, oxygen, nitrogen 

Fat: carbon, hydrogen, oxygen

Na⁺ + Cl → NaCI

Magnesium hydroxide and a mild base (baking soda).

(i) A - Carbon (C); B - Carbon monoxide (CO) C - Carbon dioxide (COr).

(ii) Carbon (or A) has atomic number 6. Its electronic configuration is 2,4. It is present in 14^th group of the periodic table.

1. Alkaline

2. They neutralize acid in the stomach.

Answer is Na⁺ Cl^-

NaOH + HCl → NaCl + H₂O

Answer is H₂O (water)

(i) Hydrogen gas.

(ii) By carbon diofde gas.

(iii) Because sodium reacts violently with water and  air.

(iv) Lead, copper or gold.

(v) By painting iron articles.

Na⁺ OH^- + H⁺ Cl^- → Na⁺Cl^- + H₂O

1. No’, water is neutral

2. Increase

3. Amount OH^- increases

The answer is (c) Sour and change blue litmus to red

When HCl is added to water it is dissociated to give H⁺ ions which combines with water molecules to give H₃O⁺ and Cl^– remains after the dissociation in the solution.

Correct option: (A) 16 g of O₂ and 14 g of N₂ 

16 g O₂ has number of moles = \(\cfrac{16}{32} = \cfrac{1}{1}\)

14 g N₂ has number of moles = \(\cfrac{14}{28} = \cfrac{1}{2}\)

Number of moles are same, so number of molecules are same.

The answer is (a) H₃O⁺ + Cl^–

Acid produces Hydrogen which will combine with water molecule to produce Hydronium ion.

 The answer is (d) 2NaCl (aq) + 2H₂O (l) → 2NaOH (aq) + Cl₂(g) + H₂(g)

(ii), (iii)

(ii) 7.10 g (iii) 0.025 mol L^–1

(a) False as non metallic oxides are acidic in nature. 

(b) True 

(c) False as in a displacement reaction more reactive element displaces less reactive metal from its salt. 

(d) False as Coal is a form of carbon which is a non metal.

Non-metals react with dilute acids to produce a gas which burns with a ‘pop’ sound.

False.

The metal which is the poorest conductor of heat is-

Lead.

Number of molecules = 4.045 x 10²³

p = 700 torr = 700/760 atm

T = 27 + 273 = 300 K

R = 0.082 litre atm K^-1 mol^-1

n = {No. of molecules}/{6.023 x 10²³}

= {4.045 x 10²³}/{6.023 x 10²³} = 0.672 mol

Now, pV = nRT or V = nRT/P

or, V = {(0.672 mol) x (0.082 litre atm.mol^-1 K^-1)(300 K)}/{(700/760 atm)}

= 17.95 litres

Area of sheet = 0.8 m² = 0.8 × 10⁴ cm²

Thickness of coating 0.010 cm

Volume of copper deposited = Area × thickness

= 0.8 × 10⁴ × 0.010

= 80 cm³

Mass of copper deposited = Volume × density

= 80 × 7.2

= 576 g

\(\because\) 63.5 g of copper contain = 6.022 × 10²³ atoms

\(\therefore\) 576 g of copper will contain = \(\frac{6.022\times10^{23}}{63.5}\) x 576

= 54.62 × 10²³

= 5.462 × 10²⁴ atoms

Dalton's law of partial pressure: According to this law, "the total pressure exerted by the mixture of non-reactive gases is equal to the sum of the partial pressures of individual gases".

P_Total = P₁ + P₂ + P₃ +…. (At constant T, V) Where P_Total = Total pressures exerted by the mixture of gases. 

P_1,P_2,P₃ etc. = Partial pressure of gases 

In a mixture of gases, the pressure exerted by the individual gas is called partial pressure.

A will have stronger inter particle forces as it can be liquefied at a higher temperature.

The total pressure exerted by the mixture of non-reactive gases is equal to the sum of the partial pressures of individual gases. 

P_total = p₁ + p₂ + p₃ +…………………

The two molecules cannot come closer than distance 2r and the volume of sphere with radius 2r is four times the volume of one molecule.

Given p₁ = 760 mm Hg V₁ = 600 mL 

T₁ = 25 + 273 = 298 K  

V₂ = 640 mL and T₂ = 10 + 273 = 283K 

According to combined gas law : p₁V₁/T₁ = p₂V₂/T₂ 

or p₂ = p₁V₁ T₂/T₁ V₂ 

 putting values and calculating, we have p₂ = 676.6 mm Hg

The gas pressure would gradually become zero as molecules will gradually slow down and ultimately settle down due to constant loss of energy

Strength of the hydrogen bond is determined by the coulombic interaction between the lone-pair electrons of the electronegative atom of one molecule and the hydrogen atom of other molecule.

The two molecules cannot come closer than distance 2r and the volume of sphere with radius 2r is four times the volume of one molecule.

Strength of H bonding determined by the coulombic interaction between the electronegative atom of one molecule and H atom of other molecule.

Intermolecular forces tend to keep the molecules together but thermal energy of the molecules tends to keep them apart. The three states of matter are the result of the balance between intermolecular forces and thermal energy of the molecules.

On increasing the temperature, the kinetic energy of liquid molecules increases so that it can overcome the attractive forces between the molecules and hence liquid can flow more easily i.e. viscosity decreases. Order of increasing viscosity: hexane < water < glycerine.  

According to Boyle’s law,
P₁V₁ = P₂V₂
P₁ = 1 atm
P₂ = ?
V₁ = 20 cc
V₂ = 50 cc
P₂ =(P₁ × V₁)/V₂
P₂ = 1 × 20/ 50 = 2/ 5 atm = 0.4 atm

The volume of a given mass of a gas is inversely proportional to its pressure at constant temperature Mathematically V α 1/P. PV = constant.

A will have stronger interparticle forces as it can be liquefied at a higher temperature. 

As interparticle forces are stronger in glycerine. 

At normal temperature and pressure ( NTP ), for Ideal gas
V_molar = 293K × 0.0820 L atm/(mol-K)/1atm × 1 mol
V_molar = 2404 L

At higher temperature interparticle attraction weakens and more number of molecules escape to vapour.

(c ) since overlapping of p orbitals side wise results in formation of pi bond and x axis is being considered as internuclear axis

Viscosity is another type of bulk property defined as a liquid’s resistance to flow. When the intermolecular forces of attraction are strong within a liquid, there is a larger viscosity. Therefore, molecular forces regarding to chemical bonds should to be stronger for glycerine than water. The viscosity of water results from hydrogen bonds between the positively charged hydrogen atoms and the negatively charged oxygen atoms. Glycerine (HOH₂C-CHOH-CH₂OH) contains three hydroxyl groups, which leads to a higher number of hydrogen bonds and therefore stronger bonds between molecules have higher viscosity.

Strength of H bonding determined by the coulombic interaction between the electronegative atom of one molecule and H atom of other molecule.

The temperature at which a real gas obeys ideal gas law over an appreciable range of pressure is called Boyle’s temperature or Boyle’s point. Boyle’s point of a gas depends upon its nature. Above the Boyle’s point, real gases show positive deviations from ideality and Z values are greater than one.

T1 = 15+273 = 288K , 

V1 = 3L 

 T2 = -73 + 273 = 200 K , 

V2 = ?

 V1/T1 = V2 / T2 , V2 = ( 3 x 200) / 288 = 2.08 L. 

The deviation from ideal behaviour can be measured in terms of compressibility factor Z, which is the ratio of product PV and nRT.
Mathematically,
Z = PV/nRT
For ideal gas, Z = 1 at all temperatures and pressures because PV = n RT

At intermediate pressure, most gases have z < 1, because gases show ideal behaviour when the volume occupied is large so that the volume of the molecules can be neglected in comparison to the volume of gas. Also, gases have some force of attraction between the molecules.

At absolute zero, volume approach to zero and below this temperature, the volume will be negative, which is meaningless. Hence absolute zero is the lowest possible temperature.

The boiling point of water depends upon the pressure on its surface. It increases with increase of pressure and decreases on lowering of pressure. At higher altitudes, the atmospheric pressure is low and, therefore water boils below 100^°C. Hence, sufficient heat is not supplied for cooking the vegetables at hill stations. This difficulty may be overcome by using a pressure cooker.

The SI unit of pressure is the Pascal’s (Pa), which is equal to one Newton per square metre(N/m²)

It states that “the pressure of a given mass of a gas is directly proportional to the absolute temperature at constant volume.”

Mathematically, Pα T at constant V for a given mass of gas. 

At absolute zero ,volume approach to zero and below this temperature, the volume will be negative, which is meaningless. Hence absolute zero is the lowest possible temperature .