Put tick (√ ) against correct choice and cross ( x ) against wrong choice in the following question: Number of valence electrons in Cl− ion are:

The ions having same number of electrons are called isoelectronic ions. The above order is due to increasing order of effective nuclear charge.

Rutherford’s alpha-particle scattering experiment was responsible for the discovery of  (a) Atomic nucleus      (√ )  (b) Electron                 ( x )  (c) Proton     ...

    Isotopes of an element have  (a) the same physical properties   ( x )  (b) different chemical properties    ( x )  (c) different number of neutrons    (√ )  (d) different atomic...

Tick    (√) against i, ii, iii, viii, x Cross (×) against iv, v, vi, vii, ix

The series is as follows + 5, +9, + 13, +17 ....difference of two consecutive terms (9 – 5 = 13 – 9 = 17 – 13) is 4. Hence, 35 is...

Third number is the sum of first two numbers Hence 27 is wrong number in the series. It should be 29.

(d) The series is based on the following pattern: 2 × 3 + 5 = 11 11 × 4 – 6 = 38 38 × 5 + 7 = 197 197 × 6 –...

(a) The series is based on the following pattern : 16 + 12 = 17; not 19 17 + 22 = 21 21 + 32 = 30 30 + 42 = 46 46 + 52...

(d) The series is based on the following pattern : 7 + 9 = 16 9 + 16 = 25 16 + 25 = 41 25 + 41 = 66; 68 41 + 66 =...

(c) The series is based on the following pattern 4 × .5 = 2 2 × 1.5 = 3 ; not 3.5 3 × 2.5 = 7.5 7.5 × 3.5 = 26.25 26.25 × 4.5...