Chemistry-

#### Which alkali metal floats over cold water without any reaction?

Chemistry-General

- First group
- Fifth group
- First tr Solition series
- Fourth group

#### Answer:The correct answer is: First group4, Na, k all are less denses them water among these first group Li is very less reactive

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### Related Questions to study

chemistry-

#### The most suitable reagent of r the conversion of RCH_{2}OH → RCHO is

Refer to Comprehensive Review

#### The most suitable reagent of r the conversion of RCH_{2}OH → RCHO is

chemistry-General

Refer to Comprehensive Review

chemistry-

#### The appropriate reagent (s) for the transformation

is / are

Transformation of C = O group into CH

_{2}in the presence of Zn + Hg is called Clemmensen’s reduction and in the presence of NH_{2}- NH_{2}/OH^{-}is called Wolf-Kishner Reduction#### The appropriate reagent (s) for the transformation

is / are

chemistry-General

Transformation of C = O group into CH

_{2}in the presence of Zn + Hg is called Clemmensen’s reduction and in the presence of NH_{2}- NH_{2}/OH^{-}is called Wolf-Kishner Reductionchemistry-

#### Which one of the following will be the major product when

Is treated with dilute H_{2}SO_{4} in the presence of HgSO_{4}

#### Which one of the following will be the major product when

Is treated with dilute H_{2}SO_{4} in the presence of HgSO_{4}

chemistry-General

chemistry-

#### For which of the following molecule significant m ¹ 0

I)

II)

III)

IV)

-OH and -SH groups do not cancel their dipole moment

#### For which of the following molecule significant m ¹ 0

I)

II)

III)

IV)

chemistry-General

-OH and -SH groups do not cancel their dipole moment

chemistry-

#### Y is

#### Y is

chemistry-General

chemistry-

#### The product A is

#### The product A is

chemistry-General

chemistry-

#### X and Y are respectively

#### X and Y are respectively

chemistry-General

chemistry-

#### Identify Z in the reaction

Which undergoes Cannizaro’s reaction to give Z

#### Identify Z in the reaction

chemistry-General

Which undergoes Cannizaro’s reaction to give Z

chemistry-

#### Which is correct about the change given below

#### Which is correct about the change given below

chemistry-General

physics-

#### The radius of germanium () nuclide is measured to be twice the radius of . The number of nucleons in Ge are

Let radius of nucleus be . Then radius of germanium (Ge) nucleus will be.

Radius ofnucleus is given by

Hence,

Thus, in germanium () nucleus number of nucleons is 72.

Radius ofnucleus is given by

Hence,

Thus, in germanium () nucleus number of nucleons is 72.

#### The radius of germanium () nuclide is measured to be twice the radius of . The number of nucleons in Ge are

physics-General

Let radius of nucleus be . Then radius of germanium (Ge) nucleus will be.

Radius ofnucleus is given by

Hence,

Thus, in germanium () nucleus number of nucleons is 72.

Radius ofnucleus is given by

Hence,

Thus, in germanium () nucleus number of nucleons is 72.

physics-

#### For the given uniform square lamina , whose centre is

Let the each side of square lamina is .

So, (due to symmetry)

And (due to symmetry)

Now, according to theorem of perpendicular axis,

(i)

and

(ii)

From Eqs. (i) and (ii), we get

So,

So, (due to symmetry)

And (due to symmetry)

Now, according to theorem of perpendicular axis,

(i)

and

(ii)

From Eqs. (i) and (ii), we get

So,

#### For the given uniform square lamina , whose centre is

physics-General

Let the each side of square lamina is .

So, (due to symmetry)

And (due to symmetry)

Now, according to theorem of perpendicular axis,

(i)

and

(ii)

From Eqs. (i) and (ii), we get

So,

So, (due to symmetry)

And (due to symmetry)

Now, according to theorem of perpendicular axis,

(i)

and

(ii)

From Eqs. (i) and (ii), we get

So,

physics-

#### Four balls each of radius 10 cm and mass 1 kg, 2kg, 3 kg and 4 kg are attached to the periphery of massless plate of radius 1 m. What is moment of inertia of the system about the centre of plate?

Moment of inertia of the system about the centre of plane is given by

#### Four balls each of radius 10 cm and mass 1 kg, 2kg, 3 kg and 4 kg are attached to the periphery of massless plate of radius 1 m. What is moment of inertia of the system about the centre of plate?

physics-General

Moment of inertia of the system about the centre of plane is given by

physics-

#### A joint is formed by two identical rods and each of mass and length in the plane as shown. Its moment of inertia about axis coinciding with is

#### A joint is formed by two identical rods and each of mass and length in the plane as shown. Its moment of inertia about axis coinciding with is

physics-General

physics-

#### The approximate nuclear radius is proportional to ( is the mass number and the atomic number)

Experimentally it is found that the volume of a nucleus is directly proportional to its mass number. From this it is concluded that the density of each nucleus is uniform, it does not depend on the size of the nucleus.

It the nucleus is assumed to be a sphere of radius and its mass number is , then volume of nucleus

Thus,

Or

the radius of nucleus is directly proportional to the cube root(or power) of its mass number

Aliter

Nuclear radius

It the nucleus is assumed to be a sphere of radius and its mass number is , then volume of nucleus

Thus,

Or

the radius of nucleus is directly proportional to the cube root(or power) of its mass number

*A*.Aliter

Nuclear radius

#### The approximate nuclear radius is proportional to ( is the mass number and the atomic number)

physics-General

Experimentally it is found that the volume of a nucleus is directly proportional to its mass number. From this it is concluded that the density of each nucleus is uniform, it does not depend on the size of the nucleus.

It the nucleus is assumed to be a sphere of radius and its mass number is , then volume of nucleus

Thus,

Or

the radius of nucleus is directly proportional to the cube root(or power) of its mass number

Aliter

Nuclear radius

It the nucleus is assumed to be a sphere of radius and its mass number is , then volume of nucleus

Thus,

Or

the radius of nucleus is directly proportional to the cube root(or power) of its mass number

*A*.Aliter

Nuclear radius

maths-

#### The area bounded by y=cos x, y=x+1 and y=0 in the second quadrant is

#### The area bounded by y=cos x, y=x+1 and y=0 in the second quadrant is

maths-General