Answer:
So for your question, the Periodic Table tells us that sodium has an Atomic Number of 11, so there are 11 protons and 11 electrons. The Periodic Table tells us that sodium has an Atomic Mass of ≈23. So there are 23 - 11 = 12 neutrons.
Explanation:
Scientists will often use a(n) _________________, an object that helps explain ideas about the natural world.
The answer is model.
Answer:
Choice number two: this element is malleable and ductile.
Explanation:
A modern periodic table can be split into three sections:
(from left to right)
- Metals,
- Metalloids, and
- Nonmetals.
Based on the descriptions, section A likely refers to the metals. Section B likely refers to metalloids. Section C likely refers to nonmetals.
Metals are malleable and ductile. They are good conductors of electricity.
The reason is that in a metal, the valence electrons do not belong to some specific atom. Rather, the metal cations share these electrons. The electrons are free to move around the metal and conduct electricity.
Ionic compounds like table salt are brittle. The reason is that when an ionic compound is deshaped, ions of the same charge come directly into contact with each other. That creates repulsion and cracks the crystal. In contrast, the metal cations in a metal won't come into contact with each other. Electrons would rapidly fill the gap between these cations, so the metal won't crack. That's why unlike ionic compounds, metals are malleable and ductile.
The melting points of metals can vary significantly. Indeed, the mercury (
, a metal) is a liquid at room temperature. In contrast, tungsten (
, also a metal) won't melt until it is heated to over
.
Answer:
CH3(CH2)8CH3 > CH3CH2CH2CH3 > CH3CH3 (Option f)
Explanation:
Larger and heavier atoms and molecules exhibit stronger dispersion forces than smaller and lighter ones. In a larger atom or molecule, the valence electrons are, on average, farther from the nuclei than in a smaller atom or molecule. They are less tightly held and can more easily form temporary dipoles.
CH3CH3 has a molar mass of 30.07 g/mol
CH3(CH2)8CH3 has a molar mass of 142.28 g/mol
CH3CH2CH2CH3 has a molar mass of 58.12 g/mol
CH3(CH2)8CH3 > CH3CH2CH2CH3 > CH3CH3 (Option f)