Atomic Structure , Periodic table and Water Test

(Q.1)  Write the significance of the symbol of an element. (Any two)

(Q.2)  a) How will you name an element showing two different valencies?
b) Name the ions fe²⁺ and Fe³⁺.

(Q.3)  Write the chemical names of elements represented by following symbols
(i) Na   (ii) B    (iii) Fe  (iv) Cu  (v) Cl  (vi) K

(Q.4)  Find the valency of phosphorus in P₂O_3.

(Q.5)  Write two examples each of the following
(i) Monovalent cation  (ii) Monovalent anion  (iii) Divalent cation  (iv) Divalent anion

(Q.6)  (i) What is an ion?
(ii) Distinguish between anion and cation.
(iii) What is a radical?
(iv) Give two examples of basic trivalent radical.
(v) Write two examples of acidic trivalent radical.

(Q.7)  Calculate the relative molecular masses of the following compounds
(i) Cane sugar (C₁₁H₂₂O₁₁)

(Q.8)  Write the name and formula of a compound formed by
(i) Two non-metals
(ii)Two elements and oxygen
(iii)A metal and a non-metal

(Q.1)  What is water pollution?

(Q.2)  What is the chemical name and chemical formula of water?

(Q.3)  What is thermal pollution? What is the reason for this pollution?

(Q.4)  Name a metal that reacts with steam.

(Q.5)  (i)Boiling point of pure water is 100 C. What would be the effect on boiling point of water if small amount of sodium chloride is added to it?
 

(Q.6)  Where can we cook food quickly: Shimla or Delhi? Give reasons.

(Q.7)  Generally, matter expands on heating and contracts on cooling, but water shows anomalous behavior.
(i)�Describe the anomalous behavior of water.
(ii)�Draw a graph showing that water has the maximum density at 4 C.
(iii)�Write two consequences of anomalous expansion of water.

(Q.8)  What are the main sources of thermal pollution?

(Q.9)  Name any two water borne diseases.

(Q.10)  Name the shell closest to the nucleus of an atom.

(Q.11)  Atomic numbers of element A, B and C are 17, 11 and 18 respectively. Which one is metal?

(Q.12)  Draw diagrams representing the atomic structures of the following:

(i) Carbon atom (ii) Neon atom

(Q.13)  Write down:
(i) The mass number of an atom having 16 neutrons and 15 protons.
(ii) The number of neutrons in the nucleus of an atom having atomic number 5 and mass number 11

(Q.14)  Name and draw the isotopes of hydrogen.

(Q.15)  Elements X and Y have atomic numbers 9 and 11 respectively. Which of these will form
(a) A cation?

(b) An anion?
Explain with reasons.

(Q.16)  Complete the following table:

Element Symbol	Atomic Number	Mass Number	No. of Neutrons	No. of Electrons	No. of Protons
B	5	-	5	5	-
Si	-	28	-	14	14
Na	11	-	12	-	11
Cl	-	35	-	17	17
P	15	-	16	15	-

(Q.17)  Who discovered anode rays?

(Q.18)  Who discovered proton? Write any two characteristics of proton.

(Q.19)  Write properties of cathode rays.

(Q.20)  Name the metal that Rutherford used for his alpha-particle scattering experiment.

(Q.21)  Why is an atom neutral?

(Q.22)  Which part of atom was discovered by Rutherford?

(Q.23)   Write electronic configuration of Magnesium.

(Q.24)  Describe Rutherford's model of the atom.

(Q.25)  Write two differences between Dalton’s atomic theory and Modern atomic theory.

(Q.26)  How is Bohr’s atomic model different from that of Rutherford’s?

(Q.27)  Name two elements containing only one orbit.

(Q.28)  Distinguish between sodium atom and sodium ion.(Any 2 points)

(Q.29)  Which type of boding is present in sodium chloride? Explain briefly.