1. Who is credited with the modern periodic table arrangement?
Answer:
Explanation:
Moseley, through his work on X-ray wavelengths of elements, proposed the modern arrangement based on atomic numbers.
2. Which property of elements is a periodic function of their atomic numbers?
Answer:
Explanation:
All listed properties show a periodic trend with respect to atomic numbers.
3. Which block of the periodic table contains the alkali metals?
Answer:
Explanation:
Alkali metals belong to the s-block of the periodic table.
4. Which of the following is a noble gas?
Answer:
Explanation:
Neon is a noble gas known for its low reactivity.
5. The atomic radius generally ________ across a period from left to right.
Answer:
Explanation:
Due to an increase in nuclear charge, atomic size generally decreases from left to right across a period.
6. Which of the following elements is a metalloid?
Answer:
Explanation:
Silicon shows properties of both metals and non-metals, making it a metalloid.
7. Ionization energy generally ________ down a group.
Answer:
Explanation:
As atomic size increases down a group, ionization energy generally decreases.
8. Which element has the highest electronegativity?
Answer:
Explanation:
Fluorine has the highest electronegativity value on the periodic table.
9. Elements in the same group have the same number of:
Answer:
Explanation:
Elements in the same group have similar outer shell electron configurations and thus the same number of valence electrons.
10. The d-block elements are also known as:
Answer:
Explanation:
The d-block elements are commonly referred to as transition metals.
11. Which of the following elements is an actinide?
Answer:
Explanation:
Uranium is an actinide, part of the f-block elements.
12. The property of an element to attract and hold shared electrons is called:
Answer:
Explanation:
Electronegativity refers to the ability of an atom to attract and hold onto shared electrons.
13. Which of the following has the largest atomic radius?
Answer:
Explanation:
As we move from left to right across a period, atomic radius generally decreases. So, Li has the largest radius.
14. Inert gases have:
Answer:
Explanation:
Inert gases have stable electronic configurations, hence they have low electron affinity and high ionization energy.
15. Which period of the periodic table has 32 elements?
Answer:
Explanation:
The 6th period contains 32 elements, including the lanthanides.
16. An element with atomic number 12 belongs to which group?
Answer:
Explanation:
The element with atomic number 12 is magnesium (Mg) and it belongs to group 2.
17. Which of the following is a halogen?
Answer:
Explanation:
Bromine is a halogen and belongs to group 17 of the periodic table.
18. The vertical columns in the periodic table are called:
Answer:
Explanation:
The vertical columns in the periodic table are termed as groups.
19. Which element is located at the center of the periodic table?
Answer:
Explanation:
Iron is located centrally in the d-block of the periodic table.
20. The property due to which atoms of an element can form chains or rings is called:
Answer:
Explanation:
Catenation is the ability of an element to form chains or rings with atoms of the same element.