Answer: The correct answer is the option: B. An element with eight valence electrons is chemically unstable.
Explanation:
Hello! Let's solve this!
We will analyze each of the options:
A. The group number of the element provides a clue to the number of valence electrons: it is correct, since it provides the number of valence electrons.
B. An element with eight valence electrons is chemically unstable: this is not correct, since elements with eight electrons in the valence shell cannot react because they already have the last complete shell. Therefore, they are chemically stable.
C. The points must be placed one at a time on each side of the chemical symbol: it is correct, because that is the way to make the point diagram.
D. An atom is chemically stable if all the points are paired: this is correct since this verifies that the point diagram has been done well.
We conclude that the correct answer is the option: B. An element with eight valence electrons is chemically unstable.
Hope this helps..... Stay safe and have a Merry Christmas!!!!!!!!! :D
Answer: D (The abundance percentage of each isotope)
Explanation: hope this helps!
Hey there!
Na + H₂O → NaOH + H₂
First, balance O.
One on the left, one on the right. Already balanced.
Next, balance H.
Two on the left, three on the right. Let's add a coefficient of 2 in front of NaOH and a coefficient of 2 in front of H₂O, so we have 4 on each side.
Na + 2H₂O → 2NaOH + H₂
Lastly, balance Na.
One on the left, two on the right. Add a coefficient of 2 in front of Na.
2Na + 2H₂O → 2NaOH + H₂
This is our final balanced equation.
Hope this helps!
Answer:
The volume on the tank is 6, 20 L
Explanation:
We use the formula PV=nRT. We convert the units of pressure in kPa into atm and temperature in Celsius into Kelvin:
0°C=273K
101,325kPa---1 atm
275kPa --------x=(275kPax 1 atm)/101,325kPa= 2,71 atm
PV=nRT --> V=nRT/P
V= 0,750 mol x 0,082 l atm /K mol x 273 K/ 2, 71 atm= <em>6, 20 L</em>
If the number of valence electron is one than it will be placed in group IA. elements of group IIA will have two valence electrons and so on....
