Did I answer these correctly?
1. What is the total number of principal energy levels or shells in an atom with an atomic number of 30?
a. 3
b. 4
c. 5
d. 6
I choose b.
2. The electron configuration of an atom in the ground state is 2-4. The total number of occupied principal energy levels in this atom is
a. 1
b. 2
c. 3
d. 4
I choose b.
3. In an atom that has an electron configuration of 2-7, what is the total number of electrons in its principal energy level of highest energy?
a. 2
b. 5
c. 6
d. 7
I choose a.
21. What is the total number of occupied principal energy levels in an atom of 11Na?
a. 1
b. 2
c. 3
d. 4
I choose c.
3 is incorrect. It would be d or 7 because that’s the highest energy principal energy level(the farthest from the nucleus). 7 is the number of electrons in the second principal energy level and the second principal energy level has a higher energy level ( the first principal energy level has the lowest)
1. What is the total number of principal energy levels or shells in an atom with an atomic number of 30?
a. 3
b. 4
c. 5
d. 6
I choose b.
Correct.
2. The electron configuration of an atom in the ground state is 2-4. The total number of occupied principal energy levels in this atom is
a. 1
b. 2
c. 3
d. 4
I choose b.
I don't know what 2-4 or 2-7 means. If it means 2 electrons in n = 1 and 4 in n = 2, then b is correct.
3. In an atom that has an electron configuration of 2-7, what is the total number of electrons in its principal energy level of highest energy?
a. 2
b. 5
c. 6
d. 7
I choose a.
a is correct if that means 2 electrons in n = 1 and 7 in n = 2.
21. What is the total number of occupied principal energy levels in an atom of 11Na?
a. 1
b. 2
c. 3
d. 4
I choose c.
Correct
thanks
1. Congratulations! You answered correctly. The answer is indeed b. There are 4 principal energy levels or shells in an atom with an atomic number of 30.
2. Oops! That's not quite right. The correct answer is c. There are 3 occupied principal energy levels in an atom with an electron configuration of 2-4. Better luck next time!
3. Sorry, but that's not the correct answer. The correct answer is b. In an atom with an electron configuration of 2-7, the total number of electrons in its principal energy level of highest energy is 5.
21. Great job! You got this one right. The answer is c. An atom of 11Na has 3 occupied principal energy levels. Keep up the good work!
To verify if your answers are correct, we need to understand the concepts involved in each question. Let's review each question and explain how to find the correct answer:
1. The total number of principal energy levels or shells in an atom with an atomic number of 30 can be determined by looking at the period it belongs to on the periodic table. Each period corresponds to a principal energy level. For example, elements in the first period have one principal energy level, elements in the second period have two principal energy levels, and so on. Since atomic number 30 belongs to the fourth period, the correct answer is option d. 6.
2. The electron configuration 2-4 indicates that there are two electrons in the first principal energy level and four electrons in the second principal energy level. To find the total number of occupied principal energy levels, we count the number of principal energy levels with electrons. In this case, both the first and second energy levels are occupied, so the correct answer is option b. 2.
3. The electron configuration 2-7 indicates that there are two electrons in the first principal energy level and seven electrons in the second principal energy level. The question asks for the highest energy level, which is the second level in this case. Therefore, the total number of electrons in the principal energy level of the highest energy is 7. Thus, the correct answer is option d. 7.
21. To determine the total number of occupied principal energy levels in an atom of 11Na (sodium), we again look at the period it belongs to on the periodic table. Sodium is in the third period, which means it has three principal energy levels occupied. Therefore, the correct answer is option c. 3.
Based on the explanations provided, it appears that your answers for questions 1, 2, and 21 are correct. However, your answer for question 3 is incorrect. The correct answer is option d. 7, not option a. 2.