Question

q1 chemistry: u2l15 electron config day 5
teacher:
date:
name:
as a laxative. the pill they took made of this element passed through their digestive tracks, and it was recovered after passing, cleaned, and used again, giving it the name \the everlasting pill.\
which of the following electron configurations represents the most likely metal used in this \everlasting pill\? explain, and identify the element in your response.
a. kr5s²4d¹⁰5p³
b. xe6s²4f¹⁴5d¹⁰6p⁴
c. ne3s²3p²

1. **element a and b are two elements that have similar properties. they are both soft enough to be cut with a knife, but when you place them in a sample of water, they react violently. initially, the samples are lustrous (shiny), but after sitting out in the air for a while, the samples turn dull - gray in color as they react with oxygen. which pair most likely represents these 2 elements, and how do you know?

set 1
set 2
set 3
element a
1s²2s²2p⁶3s¹
1s²2s²2p⁶3s²3p⁴
1s²2s²2p⁵
element b
1s²2s²2p⁶3s²3p⁶4s¹
1s²2s²2p⁶3s²3p⁵
1s²2s²2p⁶3s²3p⁵

1. a semiconductor material has an electrical conductivity falling between that of a conductor, like copper, and an insulator, like glass. as a semiconductor increases in temperature, its resistance (measure of the difficulty to pass an electric current through) decreases. semiconductors are found in laptops, scanners, and cell phones. in class, you learn that a common semiconductor is silicon. your teacher asks what another semiconductor might be, and she calls on 2 students. read their responses below and evaluate.

student a: i think another semiconducting material might be phosphorus. it is in the same row as silicon, so it has a similar electron configuration - ne3s²3p² for silicon and ne3s²3p³ for phosphorus.
student b: i disagree - i think another semiconductor might be germanium. this element is in the same family as silicon and therefore has the same number of valence electrons (4 e -).
be uncommon. change history.
which topic are you b -

Explanation:

Question 1

Step1: Analyze the properties of the "Everlasting Pill" metal

The metal is used as a laxative and can be recovered, cleaned and reused. We need to identify the element from the electron - configurations.

Step2: Recall the properties of elements from electron - configurations

• Option a: $[Kr]5s^{2}4d^{10}5p^{3}$ represents antimony (Sb). Antimony has some uses in medicine but is not typically used as a laxative in this context.
• Option b: $[Xe]6s^{2}4f^{14}5d^{10}6p^{4}$ represents polonium (Po), which is radioactive and not suitable for such a use.
• Option c: $[Ne]3s^{2}3p^{2}$ represents silicon (Si). Silicon is a non - metal and not a metal used as a laxative. None of these seem to be correct based on common knowledge of elements used as laxatives. However, if we assume the question has some error or we consider bismuth (which is sometimes used as a laxative), its electron - configuration is $[Xe]4f^{14}5d^{10}6s^{2}6p^{3}$. But among the given options, there is no correct answer.

Question 4

Step1: Analyze the properties of elements A and B

Elements A and B are soft, reactive with water and oxygen. Elements with such properties are alkali metals.

Step2: Identify alkali metals from electron - configurations

The electron - configuration of an alkali metal has one valence electron in the outermost s - orbital.

• For Element A: The electron - configuration $1s^{2}2s^{2}2p^{6}3s^{1}$ represents sodium (Na), an alkali metal.
• For Element B: The electron - configuration $1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}4s^{2}3d^{10}4p^{6}5s^{1}$ represents rubidium (Rb), an alkali metal. So Set 1 is the correct pair.

Question 5

Step1: Understand the properties of semiconductors

Semiconductors have electrical conductivity between that of conductors and insulators. Their conductivity changes with temperature.

Step2: Evaluate student responses

• Student A: Phosphorus has an electron - configuration of $[Ne]3s^{2}3p^{3}$. It is not a semiconductor. Phosphorus is a non - metal and is often used as a dopant in semiconductors but is not a semiconductor itself.
• Student B: Germanium has an electron - configuration of $[Ar]3d^{10}4s^{2}4p^{2}$. Germanium is a well - known semiconductor and is in the same group as silicon (Group 14), having the same number of valence electrons (4). So Student B is correct.

Answer:

Question 1: No correct answer among given options
Question 4: Set 1
Question 5: Student B is correct.