Answer:
Your just in luck my friend we just finished learning about that.
Explanation:
Melting
Answer:
is what a model answer key
Fluorine has C seven valence electrons.
Valence electrons are the electrons that are found on the outer shell of an atom that are capable of participating in chemical reactions. The easiest way to figure out how many valance electrons Fluorine has would be to look it up in a periodic table and notice that it a group 7 element and therefore has 7 valence electrons.
The other way to tell that Fluorine has 7 valence electrons is to notice that an element with an atomic number of 9 has 9 electrons. The electronic configuration of elements has the first 2 electrons go on the first shell or energy level 
, the leaving the next 7 to go to the second shell 
which can take up to 8 electrons.
This means that Fluorine has 7 seven valence electrons.
In a <u>Saturated </u>solution, the rate of dissociation equal to the rate of crystallization
Explanation:
A saturated solution is one than cannot dissolve any more solute because the solutes inter-molecular spaces are filled with the solute molecules at that temperature. When an attempt is made to dissolve more solute into the solution, the rate at which the solute is dissolved into the solution is equal to the rate at which excess solute is precipitated and crystallized.
Answer:
1.57×10²³ molecules
Explanation:
Given data:
Number of molecules of ethanol = ?
Volume of ethanol = 15.0 mL
Density of ethanol = 0.789 g/mL
Solution:
Mass of ethanol :
Density = mass/ volume
0.789 g/mL = mass/ 15.0 mL
Mass = 0.789 g/mL× 15.0 mL
Mass = 11.84 g
Number of moles of ethanol:
Number of moles = mass/molar mass
Number of moles = 11.84 g / 46.07 g/mol
Number of moles = 0.26 mol
1 mole contain 6.022×10²³ molecules
0.26 mol × 6.022×10²³ molecules / 1mol
1.57×10²³ molecules
