Elements X, Y and Z have atomic numbers 6, 9 and 12 respectively. Which one :
forms an anion

Elements X, Y and Z have atomic numbers 6, 9 and 12 respectively. Which one : forms a cation

Elements X, Y and Z have atomic numbers 6, 9 and 12 respectively. Which one : has four electrons in the valency shell ?

Elements A, B and C have atomic numbers 9, 20 and 10 respectively. State which one is : (i) a non-metal (ii) a metal (iii) chemically inert.

Elements A, B and C have atomic numbers 9, 20 and 10 respectively. Write down the formula of the compound formed by two of the above elements.

Three elements 'X', 'Y' and 'Z' have atomic numbers 18, 19 and 20 respectively. How many electrons are present in the M shell of these elements?

Three elements X , Y and Z have atomic numbers 19 , 37 and 55 respectively . Then the correct statement (s) is / are

The elements A, B, C, D and E have atomic number 9, 11, 17, 12 and 13 respectively. Which pair of elements belongs to the same group ?

Four elements P, Q, R and S have atomic numbers 12, 13, 14 and 15 respectively. Answer the following questions giving reasons: (i) What is the valency of Q ? (ii) Classify these elements as metals and non-metals. (iii) Which of these elements will form the most basic oxide?

In group 1 of the periodic table three elements X, Y and Z have atomic radii 133 pm, 95 pm and 65 pm respectively. Giving a reason, arrange them in the order of increasing atomic number in the group.

A compound contains three elements X, Y and Z. The oxidation number of X, Y and Z are +3, +5 and -2 respectively. The possible formula of the compound is