Science (English Medium) कक्षा १२ - CBSE Question Bank Solutions

 Draw structures of the following: 
XeF₄ 

Draw the structure of XeF₄. 

Which of the following fluorides does not exist?

Partial hydrolysis of XeF₄ gives ____________.

Helium is preferred to be used in balloons instead of hydrogen because it is ____________.

In which of the following pairs, the two species are isostructural:

Which of the following reactions is an example of redox reaction?

Match the compounds given in Column I with the hybridisation and shape given in Column II and mark the correct option. 

Substance having the lowest boiling point ______.

On partial hydrolysis, XeF₆ gives ______.

Account for the following : 
Although Fluorine has less negative electron gain enthalpy yet F₂ is a strong oxidizing agent.

Write the type of C++ token (keywords) and the User-defined identifier from the following.

1) else

2) Long

3) 4Queue

4) _count

Rewrite the following C++ code after removing any/all syntactical error with each correction underline

Note: Assume all required header files are already included in the program.

Typedef Count(int);
void main()
(
    Count C;
    cout<<"Enter the count:";
    cin>>C;
    for (K = 1 ; K<=C;K++)
        cout<< C "*" K <<end1;
}

Write the type of C++ tokens (keywords and user-defined identifiers) from the following:

1) new

2) While

3) case

4) Num_2

Rewrite the following C++ code after removing any/all syntactical errors with each correction underlined.

Note: Assume all required header files are already being included in the program.

void main()
{
     cout<<"Enter an Alphabet:" ;
     cin>>CB ;
     switch(CH)
     case 'A' · cout<<"Ant"; Break ;
     case 'B' · cout<<"Bear"; Break;
}

Find the correct identifiers out of the following, which can be used for naming Variable, Constants or Functions in a C++ program.

For, while, INT, NeW, delete, lstName, Add+Subtract, namel

Observe the following C++ code very carefully and rewrite it after removing any/all syntactical errors with each correction underlined.

Note: Assume all required header files are already being included in the program

#Define float MaxSpeed=60.5;
void main()
{
   int MySpeed
   char Alert='N';
   cin>>MySpeed;
   if MySpeed>MaxSpeed
    Alert='Y';
    cout<<A1ert<<endline;
}

Write the output of the following C++ program code :

Note: Assume all required header files are already being included in the program.

void Location(int &X,int Y=4)
{
   Y+=2;
   X+=Y;
}
void main()
{
   int PX=l0,PY=2;
   Location(PY);
   cout<<PX<<","<<PY<<endl;
   Location(PX,PY);
   cout<<PX<<", "<<PY<<endl;
}

Write the output of the following C++ program code:

Note: Assume all required header files are already being included in the program.

class Eval
{
   char Level;
   int Point;
public:
   Eval(){Level='E'; Point=O;}
   void Sink(int L)
   {
      Level~=L;
   }
   void Float(int L)
   {
      Level+=L;
      Point++;
   }
   void Show()
   {
      cout<<Level<<"#"<<Point<<endl;
   }
};

void main ()
{
   Eval E;
   E.Sink(3);
   E.Show();
   E.Float(7);
   E.Show();
   E.Sink(2);
   E.Show();
}