Which of the following statements are true?
A. Unlike Ga that has a very high melting point, Cs has a very low melting point.
B. On Pauling scale, the electronegativity values of N and C are not the same.
C. $Ar, K^{+}, Cl^{–}, Ca^{2+} and S^{2–}$ are all isoelectronic species.
D. The correct order of the first ionization enthalpies of Na, Mg, Al, and Si is Si $>$ Al $>$ Mg $>$ Na.
E. The atomic radius of Cs is greater than that of Li and Rb.
Choose the correct answer from the options given below:
For the reaction A(g) $\rightleftharpoons$ 2B(g), the backward reaction rate constant is higher than the forward reaction rate constant by a factor of 2500, at 1000 K.
[Given: R = 0.0831 atm $mol^{–1} K^{–1}$]
$K_p$ for the reaction at 1000 K is:
Among the following, choose the ones with an equal number of atoms.
Choose the correct answer from the options given below:
Identify the suitable reagent for the following conversion: $Ph-C(=O)-OCH_3$ $\longrightarrow$ $Ph-CHO$
List-I | List-II | ||
| (A) | mI | (I) | Shape of orbital |
| (B) | ms | (II) | Size of orbital |
| (C) | I | (III) | Orientation of orbital |
| (D) | n | (IV) | Orientation of spin of electron |
Gadolinium has a low value of third ionisation enthalpy because of
The element expected to form largest in achieve the nearest noble gas configuration.
A constant voltage of 50 V is maintained between the points A and B of the circuit shown in the figure. The current through the branch CD of the circuit is :
Which of the following statements are true?
A. Unlike Ga that has a very high melting point, Cs has a very low melting point.
B. On Pauling scale, the electronegativity values of N and C are not the same.
C. $Ar, K^{+}, Cl^{–}, Ca^{2+} and S^{2–}$ are all isoelectronic species.
D. The correct order of the first ionization enthalpies of Na, Mg, Al, and Si is Si $>$ Al $>$ Mg $>$ Na.
E. The atomic radius of Cs is greater than that of Li and Rb.
Choose the correct answer from the options given below:
AB is a part of an electrical circuit (see figure). The potential difference \(V_A - V_B\), at the instant when current \(i = 2\) A and is increasing at a rate of 1 amp/second is:
Modern Periodic Table is the tabular arrangement of the elements in increasing order of their atomic numbers. It is commonly referred to as the Long Form of the Periodic Table and is based on the modern periodic law and is the tabular arrangement of elements in increasing order of their atomic numbers (Z).

*Numbering system adopted by the International Union of Pure and Applied Chemistry (IUPAC).
The periodic table of elements is as follows:
| Atomic number (Z) | Symbol | Name |
| 1 | H | Hydrogen |
| 2 | He | Helium |
| 3 | Li | Lithium |
| 4 | Be | Beryllium |
| 5 | B | Boron |
| 6 | C | Carbon |
| 7 | N | Nitrogen |
| 8 | O | Oxygen |
| 9 | F | Fluorine |
| 10 | Ne | Neon |
| 11 | Na | Sodium |
| 12 | Mg | Magnesium |
| 13 | Al | Aluminium |
| 14 | Si | Silicon |
| 15 | P | Phosphorus |
| 16 | S | Sulfur |
| 17 | Cl | Chlorine |
| 18 | Ar | Argon |
| 19 | K | Potassium |
| 20 | Ca | Calcium |
| 21 | Sc | Scandium |
| 22 | Ti | Titanium |
| 23 | V | Vanadium |
| 24 | Cr | Chromium |
| 25 | Mn | Manganese |
| 26 | Fe | Iron |
| 27 | Co | Cobalt |
| 28 | Ni | Nickel |
| 29 | Cu | Copper |
| 30 | Zn | Zinc |
| 31 | Ga | Gallium |
| 32 | Ge | Germanium |
| 33 | As | Arsenic |
| 34 | Se | Selenium |
| 35 | Br | Bromine |
| 36 | Kr | Krypton |
| 37 | Rb | Rubidium |
| 38 | Sr | Strontium |
| 39 | Y | Yttrium |
| 40 | Zr | Zirconium |
| 41 | Nb | Niobium |
| 42 | Mo | Molybdenum |
| 43 | Tc | Technetium |
| 44 | Ru | Ruthenium |
| 45 | Rh | Rhodium |
| 46 | Pd | Palladium |
| 47 | Ag | Silver |
| 48 | Cd | Cadmium |
| 49 | In | Indium |
| 50 | Sn | Tin |
| 51 | Sb | Antimony |
| 52 | Te | Tellurium |
| 53 | I | Iodine |
| 54 | Xe | Xenon |
| 55 | Cs | Caesium |
| 56 | Ba | Barium |
| 57 | La | Lanthanum |
| 58 | Ce | Cerium |
| 59 | Pr | Praseodymium |
| 60 | Nd | Neodymium |
| 61 | Pm | Promethium |
| 62 | Sm | Samarium |
| 63 | Eu | Europium |
| 64 | Gd | Gadolinium |
| 65 | Tb | Terbium |
| 66 | Dy | Dysprosium |
| 67 | Ho | Holmium |
| 68 | Er | Erbium |
| 69 | Tm | Thulium |
| 70 | Yb | Ytterbium |
| 71 | Lu | Lutetium |
| 72 | Hf | Hafnium |
| 73 | Ta | Tantalum |
| 74 | W | Tungsten |
| 75 | Re | Rhenium |
| 76 | Os | Osmium |
| 77 | Ir | Iridium |
| 78 | Pt | Platinum |
| 79 | Au | Gold |
| 80 | Hg | Mercury |
| 81 | Tl | Thallium |
| 82 | Pb | Lead |
| 83 | Bi | Bismuth |
| 84 | Po | Polonium |
| 85 | At | Astatine |
| 86 | Rn | Radon |
| 87 | Fr | Francium |
| 88 | Ra | Radium |
| 89 | Ac | Actinium |
| 90 | Th | Thorium |
| 91 | Pa | Protactinium |
| 92 | U | Uranium |
| 93 | Np | Neptunium |
| 94 | Pu | Plutonium |
| 95 | Am | Americium |
| 96 | Cm | Curium |
| 97 | Bk | Berkelium |
| 98 | Cf | Californium |
| 99 | Es | Einsteinium |
| 100 | Fm | Fermium |
| 101 | Md | Mendelevium |
| 102 | No | Nobelium |
| 103 | Lr | Lawrencium |
| 104 | Rf | Rutherfordium |
| 105 | Db | Dubnium |
| 106 | Sg | Seaborgium |
| 107 | Bh | Bohrium |
| 108 | Hs | Hassium |
| 109 | Mt | Meitnerium |
| 110 | Ds | Darmstadtium |
| 111 | Rg | Roentgenium |
| 112 | Cn | Copernicium |
| 113 | Nh | Nihonium |
| 114 | Fl | Flerovium |
| 115 | Mc | Moscovium |
| 116 | Lv | Livermorium |
| 117 | Ts | Tennessine |
| 118 | Og | Oganesson |
Read More: Periodic Classification of Elements