If a ball is running down a ramp, why is it that when you change the height of the ramp, the ... of the ramp, then you will increase the acceleration of a ball which rolls down the ramp.
Answer:
(a) ₁₉K: 1s² 2s² 2p⁶ 3s² 3p⁶ 4s¹
(b) ₁₀Ne: 1s² 2s² 2p⁶
---
(a) 3
(b) 6
(c) 7
Explanation:
We can state the ground-state electron configuration for each element following Aufbau's principle.
(a) ₁₉K: 1s² 2s² 2p⁶ 3s² 3p⁶ 4s¹
(b) ₁₀Ne: 1s² 2s² 2p⁶
Second part
(a) Al belongs to Group 13 in the Periodic Table. It has 13-10=3 electrons in the valence shell.
(b) O belongs to Group 16 in the Periodic Table. It has 16-10=6 electrons in the valence shell.
(c) F belongs to Group 17 in the Periodic Table. It has 17-10=7 electrons in the valence shell.
Answer:
Explanation:
Moles of sodium
=
130
⋅
g
22.99
⋅
g
⋅
m
o
l
−
1
=
5.65
⋅
m
o
l
.
Now you have the stoichiometric equation:
2
N
a
(
s
)
+
2
H
2
O
(
l
)
→
2
N
a
O
H
(
a
q
)
+
H
2
(
g
)
↑
⏐
If there are
5.65
⋅
m
o
l
of metal, clearly
5.65
⋅
m
o
l
2
dihydrogen gas are evolved......, i.e.
2.83
⋅
m
o
l
H
2
. Typically, in a question like this, you would also be asked to calculate the volume the gas occupies under standard conditions, and the
p
H
of the resultant solution (would it be high, low, neutral?).
Answer:
The youngest rock layers are at the top and the oldest are at the bottom, which is described by the law of superposition.
Explanation:
