Periodic Table MCQs set 2 for PPSC Food Inspector (BS-14) Everyday Science — 20 solved questions.
Q1. The d-block elements in the centre of the long form table are commonly known as what in exam-friendly language?
Answer: Transition metals or transition elements in many syllabi
Explanation: The d-block occupies Groups 3-12 in the centre of the periodic table and contains the transition metals, which are characterised by partially filled d-orbitals and variable oxidation states.
Q2. The two rows often shown separately below the main table contain the f-block elements frequently split into which pair of series names?
Answer: Lanthanide series and actinide series in standard charts
Explanation: The f-block elements are split into the lanthanide series (elements 57-71, period 6) and the actinide series (elements 89-103, period 7), which are displayed separately below the main periodic table.
Q3. All isotopes of a single element share which fixed identity number on the periodic table?
Answer: Atomic number
Explanation: The atomic number equals the number of protons in the nucleus and uniquely identifies each element; isotopes of the same element differ in neutron number (and thus mass number) but share the same atomic number.
Q4. A neutral chlorine atom in its ground state has 17 electrons. Using the modern long-form arrangement which period is chlorine in?
Answer: Period 3
Explanation: Chlorine has 17 electrons arranged in three electron shells (2, 8, 7), placing it in Period 3 of the periodic table. The period number corresponds to the highest principal quantum number (outermost shell) occupied by electrons in the ground state atom.
Q5. Cesium is used in precise atomic clocks partly because of atomic transitions but for grouping alone where does cesium sit on a standard chart?
Answer: Group 1 Period 6
Explanation: Caesium (Cs) has one valence electron and belongs to the alkali metals; it sits in Group 1 and, having six electron shells, it occupies Period 6 of the standard periodic table.
Q6. Neon is used in bright signage because it can glow when excited yet it is chemically reluctant under ordinary conditions. Which column is neon in?
Answer: Group 18
Explanation: Neon is a noble gas located in Group 18 (the rightmost column) of the periodic table, which contains elements with completely filled outer electron shells and therefore very low chemical reactivity.
Q7. Bromine at room temperature is a liquid nonmetal and is a textbook example of which family?
Answer: Halogens
Explanation: Bromine belongs to Group 17, the halogens, alongside fluorine, chlorine, iodine, and astatine; it is the only non-metallic element that is liquid at room temperature.
Q8. Which period includes the elements from potassium K through krypton Kr in the standard long-form table?
Answer: Period 4
Explanation: Period 4 begins with potassium (K, Z=19) and ends with krypton (Kr, Z=36), spanning 18 elements and including the first row of d-block transition metals.
Q9. Going down Group 1 from lithium to francium what is the usual trend in metallic character for the elements as simple metals?
Answer: Metallic character increases as atoms become larger and electrons are lost more easily in textbook trends
Explanation: Going down Group 1, each successive element has an additional electron shell, increasing atomic radius and decreasing ionization energy, so electrons are lost more easily and metallic character increases.
Q10. Across a period from left to right what happens to electronegativity in Pauling-style introductory trends?
Answer: It generally increases toward the right except rare formal exceptions students rarely need for MCQs
Explanation: Electronegativity generally increases across a period from left to right because the nuclear charge rises while electrons are added to the same shell, pulling bonding pairs more strongly toward each atom. Noble gases are typically excluded from standard Pauling electronegativity scales, so the trend climbs toward the halogens on the right side of the period.
Q11. When teaching diet links exam writers pair anaemia with iron in blood chemistry not with the periodic group alone. For table classification only iron Fe is best placed where?
Answer: d-block as a transition metal in Period 4 in standard charts
Explanation: Iron (Fe, atomic number 26) has an incomplete 3d subshell and is classified in the d-block as a transition metal in Group 8 and Period 4 of the standard periodic table.
Q12. Copper wiring is a familiar conductor. In the long-form table copper Cu is a classic example of which category of metals?
Answer: Transition metal in the d-block
Explanation: Copper (Cu) is a transition metal located in the d-block of the periodic table, specifically in Period 4, and it exhibits the characteristic properties of transition metals such as variable oxidation states and high electrical conductivity.
Q13. Which statement about noble gases matches typical introductory exam facts about their chemistry under ordinary lab conditions?
Answer: They are generally unreactive because their valence shell is a stable closed shell in simple terms
Explanation: Noble gases (Group 18) have completely filled valence shells, giving them very high ionisation energies and virtually no tendency to gain, lose, or share electrons under ordinary conditions.
Q14. An element has atomic number 12. How many protons does its nucleus contain and which group is magnesium commonly assigned in main-group numbering?
Answer: 12 protons and Group 2
Explanation: Atomic number equals the number of protons; magnesium has Z=12, so its nucleus contains 12 protons, and it belongs to Group 2 (alkaline earth metals) with two valence electrons.
Q15. In many basic charts aluminium is a metal on the right side of a period that also includes nonmetals like phosphorus and chlorine. Which property contrast is most typical between aluminium and chlorine across Period 3?
Answer: Aluminium is a metal and often conducts electricity well as a solid while chlorine is a nonmetal with a covalent molecular form
Explanation: Aluminium is a metal with a sea of delocalized electrons enabling electrical conductivity; chlorine is a nonmetal forming diatomic Cl₂ molecules via covalent bonds and is a poor conductor - reflecting the metal-nonmetal transition across Period 3.
Q16. The vertical groups on a long-form table were historically called families partly because members often share what kind of chemistry in introductory explanations?
Answer: Similar outer electron counts that lead to similar bonding patterns in basic textbook rules
Explanation: Elements in the same vertical group share the same number of valence electrons, which largely determines how they form bonds and react with other elements. This shared outer-electron configuration produces strikingly similar chemical behavior across the group, which is why groups were historically called families.
Q17. Fluorine is the most electronegative element in Pauling scales used in many textbooks. Where is fluorine located on the standard chart?
Answer: Group 17 Period 2
Explanation: Fluorine (F) has atomic number 9 with the electron configuration 2,7; it sits in Group 17 (halogens) and Period 2, and its small atomic radius and high nuclear charge make it the most electronegative element on the Pauling scale.
Q18. Phosphorus is important in DNA and energy carriers in biology but for the periodic table alone phosphorus P is most typically placed in which group in modern numbering?
Answer: Group 15
Explanation: Phosphorus (P) belongs to Group 15 of the modern periodic table, a group also known as the pnictogens, which includes nitrogen, arsenic, antimony, and bismuth. Its five valence electrons allow it to form the phosphate groups essential in DNA backbones and in ATP, the cell's main energy currency.
Q19. Oxygen supports combustion and life processes. In standard numbering what group is oxygen O usually assigned among main groups?
Answer: Group 16
Explanation: Oxygen belongs to Group 16 (also called the chalcogens) in the periodic table; its six valence electrons drive its strong tendency to form two covalent or ionic bonds.
Q20. Boron sits next to carbon on the chart and is often used to illustrate an element with properties between metals and nonmetals. Which class fits boron in broad wall-chart language?
Answer: Metalloid border region element in many charts
Explanation: Boron exhibits intermediate properties between metals and nonmetals - it is a semiconductor and forms covalent bonds - placing it in the metalloid (semimetal) category on most periodic tables.