Choose the correct option and rewrite the statement:i. which of the f

Choose the correct option and rewrite the statement:i. which of the following ti-lads does not follow Dobereirier’s law of triads? (a) Li, Na, K (b) Ca, Sr, Ba (c) Be, Mg, Ca (d) Cu, Ag, Auii. During Newlands time …….. elements were known. (a) 56 (b) 65 (c) 63 (d) 36iii. Halogens belong to group …….. in the modern periodic table. (a) 15 (b) 16 (c) 17 (d) 18iv. Noble gases belong to group …….. in modern periodic table. (a) 15 (b) 16 (c) 17 (d) 18v. The law of octaves was given by …….. (a) Dobereiner (b) Newlands (c) Mendeleev (d) Moseleyvi. Eka-boron was subsequently named as …….. (a) gallium (b)germanium (C) scandium (d) molybdenumvii. The halogen which is liquid at room temperature is ……… (a) fluorine (b) astatine (C) bromine (d) iodineviii. ……… is used in balloons and in scuba diving. (a) Helium (b) Oxygen (c) Nitrogen (d) Ozone

Answer»

i. (d) Cu, Ag, Au

ii. (a) 56

iii. (c) 17

iv. (d) 18

v. (b) Newlands

vi. (C) scandium

vii. (C) bromine

viii. (a) Helium