Answer :
Sure! Let's go through each of the questions one by one, explaining the reasoning behind each answer.
Question 35:
When alpha particles are sent through a thin metal foil, only one out of ten thousand of them rebound. This observation led to the conclusion that:
- a. Positively charged particles are concentrated at the center of the atom.
This aligns with the conclusion from the famous Rutherford gold foil experiment, which showed that atoms have a small, dense, positively charged nucleus.
Question 36:
The canal ray experiment led to the discovery of:
- a. protons
The canal ray experiment, conducted by Eugen Goldstein, contributed to the discovery of protons as positive particles in the atom.
Question 37:
In which of the following pairs of shells is the energy difference between two adjacent orbits minimum?
- d. N, O
The energy difference between adjacent shells decreases as you move farther from the nucleus, so the smallest difference would be between the outermost shells listed here.
Question 38:
Assertion and Reason:
- Assertion A: An electron in the inner orbit is more tightly bound to the nucleus.
- Reason B: The greater the absolute value of the energy of an electron, the more tightly the electron is bound to the nucleus.
Both statements are correct, and the reason correctly explains the assertion:
- b. Both A and B are individually correct and B is the correct reason for A.
Question 39:
If two naturally occurring isotopes of an element are [tex]\(^{15}_7X\)[/tex] and [tex]\(^{11}_7X\)[/tex] with an average atomic weight of 14, calculate their percentage composition.
The correct answer is:
- d. 65, 35
Question 40:
An element has two isotopes with mass numbers 16 and 18, and the average atomic weight is 16.5. The percentage abundance of these isotopes is:
- a. 75, 25
Question 41:
Which of the following are isobars?
- c. [tex]\(_b^a X, _{b+1}^a Y\)[/tex]
Isobars are atoms of different elements with the same atomic mass but different atomic numbers.
Question 42:
Some elements have fractional atomic masses due to:
- b. the existence of isotopes.
The fractional atomic mass is often a weighted average of the masses of the element’s isotopes, leading to a non-integer value.
These answers reflect a fundamental understanding of atomic theory and experiments that led to the development of our understanding of atomic structure.
Question 35:
When alpha particles are sent through a thin metal foil, only one out of ten thousand of them rebound. This observation led to the conclusion that:
- a. Positively charged particles are concentrated at the center of the atom.
This aligns with the conclusion from the famous Rutherford gold foil experiment, which showed that atoms have a small, dense, positively charged nucleus.
Question 36:
The canal ray experiment led to the discovery of:
- a. protons
The canal ray experiment, conducted by Eugen Goldstein, contributed to the discovery of protons as positive particles in the atom.
Question 37:
In which of the following pairs of shells is the energy difference between two adjacent orbits minimum?
- d. N, O
The energy difference between adjacent shells decreases as you move farther from the nucleus, so the smallest difference would be between the outermost shells listed here.
Question 38:
Assertion and Reason:
- Assertion A: An electron in the inner orbit is more tightly bound to the nucleus.
- Reason B: The greater the absolute value of the energy of an electron, the more tightly the electron is bound to the nucleus.
Both statements are correct, and the reason correctly explains the assertion:
- b. Both A and B are individually correct and B is the correct reason for A.
Question 39:
If two naturally occurring isotopes of an element are [tex]\(^{15}_7X\)[/tex] and [tex]\(^{11}_7X\)[/tex] with an average atomic weight of 14, calculate their percentage composition.
The correct answer is:
- d. 65, 35
Question 40:
An element has two isotopes with mass numbers 16 and 18, and the average atomic weight is 16.5. The percentage abundance of these isotopes is:
- a. 75, 25
Question 41:
Which of the following are isobars?
- c. [tex]\(_b^a X, _{b+1}^a Y\)[/tex]
Isobars are atoms of different elements with the same atomic mass but different atomic numbers.
Question 42:
Some elements have fractional atomic masses due to:
- b. the existence of isotopes.
The fractional atomic mass is often a weighted average of the masses of the element’s isotopes, leading to a non-integer value.
These answers reflect a fundamental understanding of atomic theory and experiments that led to the development of our understanding of atomic structure.
