Answer :
To determine which conclusion can be accurately made about one of the unknown elements based on the given data, we need to analyze each of the given statements:
1. Element 1:
- Density: 9 [tex]\( g/cm^3 \)[/tex]
- Melting Point: 1085 [tex]\(^{\circ}C \)[/tex]
- Boiling Point: 2927 [tex]\(^{\circ}C \)[/tex]
- Electrical Conductivity: 95
2. Element 2:
- Density: 2 [tex]\( g/cm^3 \)[/tex]
- Melting Point: 115 [tex]\(^{\circ}C \)[/tex]
- Boiling Point: 445 [tex]\(^{\circ}C \)[/tex]
- Electrical Conductivity: ~0
3. Element 3:
- Density: 5 [tex]\( g/cm^3 \)[/tex]
- Melting Point: 938 [tex]\(^{\circ}C \)[/tex]
- Boiling Point: 2820 [tex]\(^{\circ}C \)[/tex]
- Electrical Conductivity: ~0
4. Element 4:
- Density: 2 [tex]\( g/cm^3 \)[/tex]
- Melting Point: 3500 [tex]\(^{\circ}C \)[/tex]
- Boiling Point: 4027 [tex]\(^{\circ}C \)[/tex]
- Electrical Conductivity: ~0
Let's evaluate each conclusion:
- Conclusion A:
Element 1 is a metal because of its high density and high electrical conductivity.
Analysis:
- Element 1 does have a high density of 9 [tex]\( g/cm^3 \)[/tex].
- Its electrical conductivity is equally high at 95 (relative to silver = 100).
- Both these properties are characteristic of metals.
Therefore, Conclusion A can be accurately made about Element 1.
- Conclusion B:
Element 2 is a nonmetal because of its low density and low melting point.
Analysis:
- Element 2 does have a low density of 2 [tex]\( g/cm^3 \)[/tex].
- It also has a low melting point of 115 [tex]\(^{\circ}C \)[/tex].
- Both these properties are indicative of nonmetals.
Conclusion B is also valid.
- Conclusion C:
Element 3 is a metal because of its high boiling point and low electrical conductivity.
Analysis:
- Element 3 has a high boiling point of 2820 [tex]\(^{\circ}C \)[/tex].
- Metals generally have high boiling points but they do not have low electrical conductivity.
- Hence, this conclusion is incorrect, as low electrical conductivity is generally a property of nonmetals, not metals.
- Conclusion D:
Element 4 is a nonmetal because of its high melting point and low density.
Analysis:
- Element 4 has a high melting point of 3500 [tex]\(^{\circ}C \)[/tex] which is unusual for nonmetals.
- It has a low density of 2 [tex]\( g/cm^3 \)[/tex], which is typical for nonmetals.
- However, a high melting point is more characteristic of metals or metalloids, so this conclusion is questionable.
Therefore, the most accurate conclusion based on the data is Conclusion A: Element 1 is a metal because of its high density and high electrical conductivity.
So, the correct answer is:
1. Element 1 is a metal because of its high density and high electrical conductivity.
1. Element 1:
- Density: 9 [tex]\( g/cm^3 \)[/tex]
- Melting Point: 1085 [tex]\(^{\circ}C \)[/tex]
- Boiling Point: 2927 [tex]\(^{\circ}C \)[/tex]
- Electrical Conductivity: 95
2. Element 2:
- Density: 2 [tex]\( g/cm^3 \)[/tex]
- Melting Point: 115 [tex]\(^{\circ}C \)[/tex]
- Boiling Point: 445 [tex]\(^{\circ}C \)[/tex]
- Electrical Conductivity: ~0
3. Element 3:
- Density: 5 [tex]\( g/cm^3 \)[/tex]
- Melting Point: 938 [tex]\(^{\circ}C \)[/tex]
- Boiling Point: 2820 [tex]\(^{\circ}C \)[/tex]
- Electrical Conductivity: ~0
4. Element 4:
- Density: 2 [tex]\( g/cm^3 \)[/tex]
- Melting Point: 3500 [tex]\(^{\circ}C \)[/tex]
- Boiling Point: 4027 [tex]\(^{\circ}C \)[/tex]
- Electrical Conductivity: ~0
Let's evaluate each conclusion:
- Conclusion A:
Element 1 is a metal because of its high density and high electrical conductivity.
Analysis:
- Element 1 does have a high density of 9 [tex]\( g/cm^3 \)[/tex].
- Its electrical conductivity is equally high at 95 (relative to silver = 100).
- Both these properties are characteristic of metals.
Therefore, Conclusion A can be accurately made about Element 1.
- Conclusion B:
Element 2 is a nonmetal because of its low density and low melting point.
Analysis:
- Element 2 does have a low density of 2 [tex]\( g/cm^3 \)[/tex].
- It also has a low melting point of 115 [tex]\(^{\circ}C \)[/tex].
- Both these properties are indicative of nonmetals.
Conclusion B is also valid.
- Conclusion C:
Element 3 is a metal because of its high boiling point and low electrical conductivity.
Analysis:
- Element 3 has a high boiling point of 2820 [tex]\(^{\circ}C \)[/tex].
- Metals generally have high boiling points but they do not have low electrical conductivity.
- Hence, this conclusion is incorrect, as low electrical conductivity is generally a property of nonmetals, not metals.
- Conclusion D:
Element 4 is a nonmetal because of its high melting point and low density.
Analysis:
- Element 4 has a high melting point of 3500 [tex]\(^{\circ}C \)[/tex] which is unusual for nonmetals.
- It has a low density of 2 [tex]\( g/cm^3 \)[/tex], which is typical for nonmetals.
- However, a high melting point is more characteristic of metals or metalloids, so this conclusion is questionable.
Therefore, the most accurate conclusion based on the data is Conclusion A: Element 1 is a metal because of its high density and high electrical conductivity.
So, the correct answer is:
1. Element 1 is a metal because of its high density and high electrical conductivity.
