Answer:
w = -531 kJ
1. Work was done by the system.
Explanation:
Step 1: Given data
- Heat gained by the system (q): 687 kJ (By convention, when the system absorbs heat, q > 0).
- Change in the internal energy of the system (ΔU°): 156 kJ
Step 2: Calculate the work done (w)
We will use the following expression.
ΔU° = q + w
w = ΔU° - q
w = 156 kJ - 687 kJ
w = -531 kJ
By convention, when w < 0, work is done by the system on the surroundings.
Answer:
D because excited electrons fall back.....
Answer:
6
8
6
Explanation:
Isotope given:
¹⁴₆C
In specie written as this;
Superscript = Mass number
Subscript = Atomic number
To find the protons, it is the same as the atomic number;
Protons = Atomic number = 6
Neutrons have no charges;
Neutrons = Mass number - Atomic number =
Neutrons = 14 - 6 = 8
The number of electrons is the same as the atomic number = 6
The scientific form is

So, the form of scientific notation is
Here is the answer for the three of them
<span>N20 = 16 e-
</span><span>SeCl2 =20
</span><span>PBr3 = 26
Remember that t</span><span>o find the valence electrons in an atom you need to identify what group the element is in. An element in group 1A has 1 valence electron. If the element is in group 2A, then it has two valence electrons.</span>