The atomic structure of the atom contains 9 positively charged particles (protons) and 10 neutrally charged particles (neutrons) in the center of the atom in a clump called the nucleus. Those 9 negatively charged particles (electrons) are moving around outside of the nucleus.
There are 10 neutral charges, because the mass of 19 comes from the number of neutral charges plus the number of positive charges.
To calculate the number of neutral charges, subtract the positive charges from the mass (19 - 9), and you get the number of neutral charges (10).
Answer:
Approximately
.
Explanation:
Look up the density
of carbon tetrachloride,
, and glycerol:
- Density of carbon tetrachloride: approximately
. - Density of glycerol: approximately
.
Let
denote the gravitational field strength. (Typically
near the surface of the earth.) For a column of liquid with a height of
, if the density of the liquid is
, the pressure at the bottom of the column would be:
.
The pressure at the bottom of this carbon tetrachloride column would be:
.
Rearrange the equation
for
:
.
Apply this equation to calculate the height of the liquid glycerol column:
.
For the answer to the question above, I can't help you directly because I don't have a calculator right now. But I'll show you how to solve this.
<span>use the freezing point depression formula for this one: delta T = i * m * K where K is a constant, m is the molality (mol solute/kg solvent), and i is the van'hoff factor the van hoff factor is the number of ions that your salt dissociates into. Since it's an ALKALI flouride salt, how many ions? k is just a constant, you get it from a table in your textbook somewhere So you have everything to solve for the molality of the solution, once you did that, multiplying it by the mass of water to find the mols of the salt. Take the mass of the salt and divide by this mols to figure out the molar mass, and then compare it with the periodic table to identify the salt.
</span>
<u>Mole solute</u> x mass of Water = Mol solute<u>
</u>kg Solvent
then
Mass of solute x <u> 1 </u> = molar mass
mole of solute
Answer:
The element is Dysprosium.