Classification of Elements and Periodicity in Properties quiz

Who stated the law of octaves?

Eka-silicon predicted by Mendeleev is now called:

The modern periodic table is based on:

The IUPAC name of the element with Z = 120 is:

Which element has the most negative electron gain enthalpy?

The element with the highest electronegativity is:

Which of these has the largest atomic radius?

Elements of group 1 and 2 belong to the:

Which of these ions is the smallest?

Which oxide is amphoteric?

What were the limitations of Mendeleev's periodic table? (2 marks)

Why do elements in the same group show similar properties? (2 marks)

Why are noble gases placed in group 18? (2 marks)

Why is the atomic radius of a cation smaller than that of its parent atom? (2 marks)

Why does atomic radius increase down a group? (2 marks)

What are representative elements? (2 marks)

What are inner transition elements? (2 marks)

Why do transition elements show variable valence? (2 marks)

What is the diagonal relationship? (2 marks)

How does metallic character change across a period and down a group? (2 marks)

The first ionisation enthalpy of Mg is 737 kJ/mol. Calculate the energy required to ionise 4.8 g of gaseous Mg atoms to Mg+ (Mg = 24). (3 marks)

Calculate the number of elements in the 4th period using the formula of orbitals filled (4s, 3d, 4p). (3 marks)

An element has the configuration [Ar] 3d10 4s2 4p3. Find its atomic number, period, group and block. (3 marks)

The electron gain enthalpy of Cl is -349 kJ/mol. Calculate the energy released when 7.1 g of gaseous Cl atoms gain electrons (Cl = 35.5). (3 marks)

Calculate the difference in Pauling electronegativity between H (2.1) and F (4.0), and between H and Cl (3.0). Which bond is more polar? (3 marks)

Read the passage and answer the questions. Mendeleev arranged elements in horizontal rows and vertical columns of a table in order of their increasing atomic weights in such a way that the elements with similar properties occupied the same vertical column. He left gaps for elements yet to be discovered. Gallium and germanium were discovered later, and their properties matched his predictions. (i) What was Mendeleev's periodic law? (ii) What were the predicted names of gallium and germanium? (iii) Give one anomaly in Mendeleev's table. (5 marks)

Read the passage and answer the questions. The ionisation enthalpy is the energy required to remove an electron from an isolated gaseous atom in its ground state. The first ionisation enthalpy generally increases across a period, but there are exceptions. Boron has a lower value than beryllium, and oxygen lower than nitrogen. (i) Why is the value of B lower than Be? (ii) Why is the value of O lower than N? (iii) Why do noble gases have the highest values in each period? (5 marks)

Read the passage and answer the questions. Isoelectronic species are atoms and ions with the same number of electrons. For example, O2-, F-, Na+ and Mg2+ have the same number of electrons, 10. Their radii are different because of their different nuclear charges. (i) Arrange them in order of decreasing radius. (ii) Why does radius decrease as nuclear charge increases? (iii) Name one more ion isoelectronic with these. (5 marks)

Read the passage and answer the questions. The elements of period 3 form oxides of varying nature. Na2O is strongly basic and MgO is basic, Al2O3 is amphoteric, and SiO2, P4O10, SO3 and Cl2O7 are acidic. This trend is related to the change in metallic and non-metallic character across the period. (i) What is an amphoteric oxide? (ii) Why does the acidic character increase across the period? (iii) Write a reaction showing the basic nature of Na2O. (5 marks)

Read the passage and answer the questions. The first member of each group of the s- and p-blocks differs in many respects from the other members. For example, lithium and beryllium form compounds with considerable covalent character, while other members form mainly ionic compounds. Lithium shows similarities with magnesium. (i) Give two reasons for the anomalous behaviour. (ii) What is the maximum covalency of the first-period elements in the p-block? (iii) What is this similarity between Li and Mg called? (5 marks)

Trace the development of the periodic table from Dobereiner to the modern periodic law. What were the merits and demerits of Mendeleev's table? (6 marks)

Explain how electronic configurations determine the position of elements in the periodic table. Describe the s, p, d and f blocks. (6 marks)

Explain the periodic trends in atomic and ionic radii and ionisation enthalpy with reasons and examples. (6 marks)

Explain electron gain enthalpy and electronegativity and their trends. How do they relate to metallic character? (6 marks)

Explain the periodic trends in chemical properties, including valence, the nature of oxides, anomalous behaviour of second-period elements and the diagonal relationship. (6 marks)