Chemical Properties of Noble Gases

Q. In the relation Y=aCos(wt-kx), the dimensional formula for k is. (, w is omega)

Q.

Define P block elements in Modern Periodic Table

Q.

Define d-Block elements.

Q.

Is there a gas lighter than helium?

Q. meaning of - a solution of ethanol in water is 10% by volume.

Q. Select the correct statement among the following:

1. Helium has the lowest melting point and boiling point.
2. Neon, argon, krypton and xenon form clathrates.
3. Helium can diffuse through rubber, PVC and even glass.
4. All the noble gases are monoatomic.
5. All the noble gases have negative electron gain enthalpy.

Q.

Which group on the periodic table is the least reactive? Why?

Q.

Halogen which is liquid at room temperature __________.

Q.

Will ${}^{35}\mathrm{Cl}$ and ${}^{37}\mathrm{Cl}$ have different valencies? Justify your answer.

Q. The group number, number of valence electrons and valency of an element with atomic number $15$, respectively, are:

1. $16,5\text{and}2$
2. $15,5\text{and}3$
3. $16,6\text{and}3$
4. $15,6\text{and}2$

Q.

Which one of the following does not exist?

(i) $XeO{F}_4$

(ii) $Ne{F}_2$

(iii) $Xe{F}_2$

(iv) $Xe{F}_6$

Q. Although +3 oxidation state is the characteristic oxidation state of lanthanoids but cerium shows +4 oxidation state also. Why?

Q. Which of the following will contain the highest number of oxygen atoms
A) 16 gram of O atom
B) 32 gram of O2 molecule
C) 48 gram of O3 molecule
D)None, all have the same no of atoms
i saw the answer but 32gram of O2molecule means 1mole O2molecules and 48g O3molecules means 1mole of O3molecules right.therefore c should be correct. Am i right

Q. On heating with HCl, acetone gives

Q. The number of geometrical isomers found in the metal complexes $\left[Pt\right(Cl{)}_2\left(N{H}_3{)}_2\right],\left[Ni\right(CO{)}_4],[Ru\left(H_{2}O{)}_{3}C{l}_3\right]\text{and}\left[CoC{l}_2\right(N{H}_3{)}_4{]}^{+}$ respectively, are

1. 1, 1, 1, 1
2. 2, 1, 2, 2
3. 2, 1, 2, 1
4. 2, 0, 2, 2

Q. The molecular orbital configuration of a diatomic molecule is $\sigma 1s^2{\sigma }^{+}1s^2\sigma 2s^2{\sigma }^{+}2s^2{\sigma }^{+}2s^2\sigma 2p_x^2$ $\{\begin{array}{c}\pi 2p_y^2\\ \pi 2p_z^2\end{array}$ Its bond order is

1. 3
2. 2.5
3. 2
4. 1

Q.

What is the rarest element?

Q. What volume at STP of CO is required to reduce one mole of Fe2O3 in the following reaction Fe2O3 + CO = Fe + CO2

Q.

What are Lanthanides and Actinides? Of these two, which series is primarily composed of man-made elements? Why could these elements not be accommodated in the main body of the periodic table?

Q. What are noble gases? Why are they also called inert gases?

Q. Why the ccp lattice has 4 oxide ions per unit cell

Q. acetyl chloride on reduction with the( prod) lialh4 product formed i

Q.

Which elements are placed at the bottom of the periodic table?

1. Lanthanides

2. Halogens

3. Inert gases

4. Alkali metals

Q.

State four physical properties of hydrogen.

Q. Consider the following properties of the noble gases :
$I$ : They readily form compounds which are colourless
$II$ : They generally do not form ionic compounds
$III$ : Xenon has variable oxidation states in its compounds
$IV$ : The smaller $He$ and $Ne$ do not form clathrate compounds.
Select correct properties.

1. $I,II,III$
2. $II,III,IV$
3. $I,III,IV$
4. All

Q.

In gases, the intermolecular (or cohesive) forces are absent.

1. True
2. False

Q.

Name or state the following with reference to the elements of the first three periods of the periodic table.

(a)Noble gas with duplet arrangement of electrons.

(b) Metalloid in period 3

(c) Valency of elements in groups 14, 15

(d) Noble gas having electronic configuration 2, 8, 8.

(e) Group whose elements have zero valency

(f) A covalent compound formed by an element in period 2 and a halogen.

(g) Non-metallic elements present in the period 3 of group 15 and group 16

(h) An electrovalent compound formed by an alkaline earth metal and a halogen.

(i) Bridge elements of period 3 of groups 1, 2, and 13.

(j) Alkali metal in period 3 that dissolves in water giving a strong alkali.

(k)Typical elements of groups 14 and 15

(l) An alkaline earth metal in period 3.

Q.

Among the group 17 members, radioactivity is present in:

1. Fluorine

2. Astatine

3. Iodine

4. Chlorine

Q.

What nonmetals are most chemically reactive?

Q. Which is has high solubility intermolecular hydrogen bonding or intermolecular hydrogen bonding?