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Passing 2”D array to a function

#include<iostream>

using namespace std;

void display (int n[3][2])

int main()

{

int num[3][2] = { {3,4},{9,5},{7,1} };

display(num);

return 0;

}

void display(int n[3][2]);

cout<<“\n  Displaying Values”<<end1;

for(int i=0;i<3;i++)

{

for(int j=0;i<2;j++)

{

cout<<n[i][j]<<" ";

}

cout<<end1<<emd1;

}

}

Output:

Displaying Values

3 4

9 5

7 1

2 – D array memory representation have 2 types.

(c) structure member

(a) built – in data type

Structure is declared using the keyword ‘struct’. The syntax of creating a structure is given below.

struct structure_name

{

type member_name 1;

type member_name2;

}

reference_name;

An optional field reference_name can be used to declare objects of the structure type directly.

Example:

struct Student

{

long rollno;

int age;

float weight;

};

A structure variable can be passed to a function in a similar way of passing any argument that is of built – in data type.

If the structure itself is an argument, then it is called “call by value”. If the reference of the structure is passed as an argument then it is called, “call by reference”.

(b) an argument

struct student

{

long examno;

char name [50];

int marks [5];

};

(b) anonymous structure

Once objects of a structure type are declared, their members can be accessed directly. The syntax for that is using a dot(.) between the object name and the member name.

Example: student.name;

if the members are a pointer type, then is used to access the members.

Let name be a character pointer in student like char*name

It can be accessed student → name,

struct

{

long roll no;

int age;

float weight;

student;

}

The student can be referred as reference name to the above structure and the elements can be accessed like student.roll no, student.age, and student.weight.

struct student

{

int exam_no, lang, eng, phy, chem, mat, csc, total;

char name[15];

}

int main()

{

student s[20];

for(int i = 0;i<20;i++)

{

cout<<"\n Enter the exam number of student:";

cin>>s[i].exam_no.;

cout<<"\n Enter language names:";

cin>>s[i].lang;

cout<<"\ Enter name of the Student:";

cin>>s[i].Name;

}

for(int i =0;i<20; i++)

{

if (s[i],name[0]=='s')

{

cout<<"student name:"<<s[i].name;

cout<<"student Exam number";

}

}

return 0;}

(C) 4⁵

Explanation:

Given third term of G.P, T₃ = 4

To find Product of first five terms

We know that,

T_n = a r^{n – 1}

It is given that, T₃ = 4

⇒ ar^{3 – 1} = 4

⇒ ar² = 4 … (i)

Product of first 5 terms = a × ar × ar² × ar³ × ar⁴

= a⁵r^1+2+3+4

= a⁵r¹⁰

= (ar²)⁵

= (4)⁵ [from (i)]

Hence, the correct option is (C)

False

Consider the sequence 3,3,3; which is A.P. and G.P. both.

(a) b. \(\frac{a^2+b^2}{a^2-b^2}\)

Given: Third term of a G.P, T₃ = 4

∴ ar² = 4 …(i)

To find: Product of first five terms

So, First five terms are a, ar, ar², ar³ and ar⁴

∴ Product of first five terms = a × ar × ar² × ar³ × ar⁴

= a⁵r^1+2+3+4

= a⁵r¹⁰

= (ar²)⁵

= (4)⁵ [from (i)]

Ans. The third term of a G.P. is 4, the product of the first five terms is (4)⁵.

Let us consider a sequence in G.P

2, 2, 2 …(i)

If two terms are in AP then,

a₂ – a₁ = a₃ – a₂

So, let the sequence (i) is in AP, then

a₂ – a₁ = 2 – 2 = 0

and a₃ – a₂ = 2 – 2 = 0

∴ ar – a = ar² – ar

This means two sequences can be in both A.P and G.P together.

Hence, the given statement is FALSE

It is given that x, 2y, 3z are in A.P

∴ 2y – x = 3z – 2y

⇒ 2y + 2y = x + 3z

⇒ 4y = x + 3z

⇒ x = 4y – 3z …(i)

and it is also given that x, y, z are in G.P

∴ Common ratio r = y/x = z/y …(ii)

∴ y × y = x × z

⇒ y² = xz …(iii)

Putting the value of x = 4y – 3z in eq. (iii), we get

y² = (4y – 3z)(z)

⇒ y² = 4yz – 3z²

⇒ 3z² – 4yz + y² = 0

⇒ 3z² – 3yz – yz + y² = 0

⇒ 3z(z – y) – y(z – y) = 0

⇒ (3z – y)(z – y) = 0

⇒ 3z – y = 0 & z – y = 0

⇒ 3z = y & z = y but z and y are distinct numbers

z = 1/3 y & z ≠ y

z/y = 1/3

r = 1/3 [from eq. (ii)]

Hence, the correct option is (b)

(c) 4 – nitrophenol

a) Diborane is a colourless, highly toxic gas with a Boiling Point of 180K. 

b) Diborane catches fire spontaneously upon exposure to air.

Hot solution of Borax when mixed with acids like HCl or H₂SO₄ gives Boric is Acid. Colemanite (Ca₂B₆O₁₁) is a compound which prepares Ortho Boric Acid.

Because of small size of both B & H forms stable compound called Boron Hydrides. 

Colloids can be classified in three different ways:

• Physical states of dispersed phase and dispersion medium 
• Interaction or affinity of phases 
• Molecular size

Colloids:

1. Colloids contain particles of dispersed phase with diameters in the range of 2 to 500 nm. 

2. They are translucent to light. 

3. e.g. Milk, fog, etc.

Solutions: 

1. Solutions contain solute particles with diameters in the range of 0.1 to 2 nm. 

2. They are transparent or may be coloured. 

3. e.g. NaCl solution

Following are some examples of colloids observed in daily life. 

i. Blue colour of the sky: The sky appears blue to us because minute dust particles along with minute water droplets dispersed in air scatter blue light which reaches our eyes. 

ii. Blood: It is a colloidal dispersion of plasma proteins and antibodies in water arid at the same time blood is also a suspension of blood cells and platelets in water. 

iii. Soils: Fertile soils are colloidal in nature where humus acts as a protective colloid. Soil adsorbs moisture and nourishing materials due to its colloidal nature. 

iv. Fog, mist and rain:

• Mist is caused by small droplets of water dispersed in air. 
• Fog is formed whenever there is temperature difference between ground and air. 
• A large portion of air containing dust particles gets cooled below its dew point, the moisture from the air condenses on the surface of these particles which form fine droplets, which are colloidal particles and float in the air as fog or mist.

[Xe]4f¹⁴5d¹⁰6s² 6p¹

i. Colloids are heterogeneous mixtures. 

ii. The component of colloid present in the largest proportion is called dispersion medium and the other components are called dispersed phase.

iii. The particles of the dispersed phase are larger than the size of a molecule and smaller than the particles which we can see with naked eye.

e.g.

• Observe the formation of solution of salt and water. Salt dissolves completely in water and forms homogeneous system.
• On the other hand, ground coffee or tea leaves with milk form suspension.
• Between the two extremes of solution and suspension exists a large group of systems called colloidal dispersions or simply colloids.

• Colloid chemistry is the chemistry of everyday life.
• A number of substances we use in our day-to-day life are colloids. For example, milk, butter, jelly, whipped cream, mayonnaise.
• Knowledge of colloid chemistry is essential for understanding about many useful materials like cement, bricks, pottery, porcelain, glass, enamels, oils, lacquers, rubber, celluloid and other plastics, leather, paper, textiles, filaments, crayons, inks, road construction material, etc.
• In many daily processes like cooking, washing, dyeing, painting, ore floatation, water purification, sewage disposal, smoke prevention, photography, pharmacy, use of colloids is important.

Ammonia forms intermolecular H- bond. 

i – c, 

ii – a, 

iii – b

• A large number of the chemicals manufactured in industries make use of catalysts to obtain specific products. 
• The use of catalyst lowers the reaction temperature as well as energy costs significantly. Due to these advantages, catalysts are of great importance in chemical industry.

d) Boron of the Boron Family is a non-metal

(b) Non- metal

 Be 1s² 2s² 2p² 

 Mg 1s² 2s² 2p⁶ 3s² 3p

Boron. Because of its small size ,high ionization enthalpy and comparatively high electronegativity.

Boron (B) ,Aluminium (Al), Gallium (Ga) , Indium(In) and Thallium (Tl).

a) Prismatic Borax (Na₂B₄O₇.10H₂O) 

b) Octahedral Borax (Na₂B₄O₇.5H₂O) 

c) Anhydrous Sodium tetra borate (Na₂B₄O₇)

Half the distance between the nuclei of the two adjacent metal atoms in a close packed lattice of the metal is called its metallic radius. 

Van der Waals‘radius > Metallic radius > Covalent radius 

Ultra pure metals are being prepared by the Van Arkel Method. The compound so formed is then decomposed by heating to get the pure metal. Van Arkels method is used to purify crude titanium metal. It is heated with iodine to about 500K to form volatile compound.

(a) It contributes to mental peace. 

(b) It keeps the spinal cord flexible.

(a) Yama

(b) Niyam 

(c) Asana

(d) Pranayama

(e) Pratyahar

(f) Dharana

(g) Dhyana

(h) Samadhi

1. (c) a few

2. (d) gentle

3. (b) vices

4. (b) expensive

5. (d) paltry

6. (d) mediocre

7. (c) agreeable

8. (a) improbably

9. (b) superior

10. (d) drains