<span>The six noble gases that occur naturally are helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), and the radioactive radon (Rn).</span>
The muscular and skeletal system because we use our brain to move our body it sends a signal to move that muscle that we want to use
Answer:
The number of valence electrons increases from top to bottom within each group.
Explanation:
The valence electrons are the outermost shell electrons.
Therefore, the number of valence electrons does not increase from top to bottom within each of the group.
Down a group, the number of valence electrons remains the same.
For group I elements, the number of electrons is 1.
The group is the vertical arrangement of elements.
From left to right across a period, the number of valence electrons increases because you move from group to group.
Correct answers are:
- Solids can diffuse in liquids. Think of a sugar cube sitting at the bottom of a cup of tea.
- Liquids can diffuse in liquids. Think of a drop of food colouring in water
- It is the process of intermingling atoms from one substance into another.
The other answers are <em>incorrect</em> because:
- Gas molecules are far apart and diffuse rapidly.
- A solid can diffuse into another solid. Pure lead can diffuse into gold, and pure gold can diffuse into lead.
Answer:
93.5 moles N₂
Explanation:
To find the moles, you need to use the Ideal Gas Law. The equation looks like this:
PV = nRT
In this equation,
-----> P = pressure (atm)
-----> V = volume (L)
-----> n = number of moles
-----> R = constant (0.0821 atm*L/mol*K)
-----> T = temperature (K)
You can plug the given values into the equation and simplify to find moles. The final answer should have 3 sig figs to match the lowest number of sig figs among the given values.
P = 95.0 atm R = 0.0821 atm*L/mol*K
V = 224 L T = 2773 K
n = ?
PV = nRT
(95.0 atm)(224 L) = n(0.0821 atm*L/mol*K)(2773 K)
21280 = n(227.6633)
93.5 = n