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:
They all have the same number of protons but different numbers of neutrons.
Explanation:
These are called isotopes. Isotopy is the existence of two or more atoms of the same element having the same atomic number but different mass numbers due to the differences in the number of neutrons in their various nuclei.
The atomic number is the number of protons in an atom. For a neutral atom, it is the same as the number of electrons.
The mass number is the number of protons and neutrons in an atom.
silicon-28 (28Si)
silicon-29 (29Si)
silicon-30 (30Si)
All of these isotopes have an atomic number of 16
Now let us chech for the neutrons:
Number of neutrons = mass number - atomic number:
for silicon-28 (28Si) : 28-16 = 12 neutrons
silicon-29 (29Si)
: 29-16 = 13 neutrons
silicon-30 (30Si): 20-16 = 14 neutrons.
I believe it is ni . Hope this helps
The first one is the correct answer: <span>The potential energy of the products is greater than that of the reactants and the change in enthalpy is positive.<span> </span></span>
