The mass number of the atom is 21, the atomic number is 9, and the element is Fluorine. There are 9 protons, 9 electrons, 12 neutrons, and the elemental symbol is F.
<h3>Properties of an atom</h3>
For every atom:
- Protons and neutrons are located in the nucleus and the addition of both equals the mass number of atoms.
- Electrons are located outside the nucleus, in orbitals.
- Neutral atoms have the same number of electrons and protons
In the diagram:
Number of electrons = 9
Number of protons = 9
Number of neutrons = 12
Mass number = 12 + 9
= 21
Atomic number = number of protons
= 9
Element with atomic number 9 = Fluorine
Symbol of the element = F
More on atoms can be found here: brainly.com/question/1566330
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The boiling point of water can be calculated by the equation:
Where:
P = Pressure in mm Hg
Po = Atmospheric pressure in mm Hg
ΔH= heat of vaporization in kJ/mol
R = Ideal Gas Constant (J/mol-K)
To = normal boiling point in Kelvin
T = boiling point of water (K)
Our known values are:
P = 630 mm Hg
Po = 760 mm Hg
ΔH = 40.66 kJ/mol = 40.66×1000
=40660
R = 8.314 J mol⁻¹ K
⁻¹
To = 373 K
Putting these values in the equation,


Solving the equation will give:
T=370K
so, the boiling point of water is 370 K.
Because the reaction occurs between a metal and non metal
CL=2,8,7
C
Answer:
The answer would be tundra.
A rain forest has a lot of humidity because it rains a lot otherwise it wouldn't be called a rain forest.
Grassland has a somewhat high temperature and average humidity enough to keep it green and grassy hence grasslands.
A wetland has a lot of water but low temperatures. Still, humidity is water so wetlands aren't it.
Explanation:
Hope this helped.
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