Sorry I can't tell you the answer but, I can tell you something...
Dividing the mass of the water lost by the mass of hydrate used is equal to the fraction of water in the compound. Multiplying this fraction by 100 gives the percent water in the hydrate.
How to find it?
Divide the mass of the water lost by the mass of hydrate and multiply by 100. The theoretical actual percent hydration percent water can be calculated from the formula of the hydrate by dividing the mass of water in one mole of the hydrate by the molar mass of the hydrate and multiplying by 100.
The elements are identified by its aomic number and they are placed in the periodic table in ascending order of atomic number.
There is one unique element for a given atomic number.
For example, atomic number 1 identifies Hydrogen and there cannot be another different element with the same atomic number.
All the elements with atomic numbers from 1 to 118 have been discovered. So, you know that there is not room for new products with atomic number equal or less than 118.
1 mole Zn ---------- 6.02 x 10²³ atoms
0.750 moles Zn ----- ?
atoms = 0.750 * ( 6.02 x 10²³ / 1 )
= 4.515 x 10²³ atoms
hope this helps!
Answer:
The concentration of a saturated solution of CuF₂ in aqueous 0.20 M NaF is 4.0×10⁻⁵ M.
Explanation:
Consider the ICE take for the solubility of the solid, CuF₂ as:
CuF₂ ⇄ Cu²⁺ + 2F⁻
At t=0 x - -
At t =equilibrium (x-s) s 2s
The expression for Solubility product for CuF₂ is:
![K_{sp}=\left [ Cu^{2+} \right ]\left [ F^- \right ]^2](https://tex.z-dn.net/?f=K_%7Bsp%7D%3D%5Cleft%20%5B%20Cu%5E%7B2%2B%7D%20%5Cright%20%5D%5Cleft%20%5B%20F%5E-%20%5Cright%20%5D%5E2)


Given s = 7.4×10⁻³ M
So, Ksp is:


Ksp = 1.6209×10⁻⁶
Now, we have to calculate the solubility of CuF₂ in NaF.
Thus, NaF already contain 0.20 M F⁻ ions
Consider the ICE take for the solubility of the solid, CuF₂ in NaFas:
CuF₂ ⇄ Cu²⁺ + 2F⁻
At t=0 x - 0.20
At t =equilibrium (x-s') s' 0.20+2s'
The expression for Solubility product for CuF₂ is:
![K_{sp}=\left [ Cu^{2+} \right ]\left [ F^- \right ]^2](https://tex.z-dn.net/?f=K_%7Bsp%7D%3D%5Cleft%20%5B%20Cu%5E%7B2%2B%7D%20%5Cright%20%5D%5Cleft%20%5B%20F%5E-%20%5Cright%20%5D%5E2)

Solving for s', we get
<u>s' = 4.0×10⁻⁵ M</u>
<u>The concentration of a saturated solution of CuF₂ in aqueous 0.20 M NaF is 4.0×10⁻⁵ M.</u>
Answer : The number of moles of argon gas is, 11.5 mol
Explanation :
To calculate the moles of argon we are using ideal gas equation as:

where,
P = pressure of argon gas = 658 mmHg = 0.866 atm (1 atm = 760 mmHg)
V = volume of argon gas = 30.6 L
n = number of moles of argon gas = ?
R = gas constant = 0.0821 L.atm/mol.K
T = temperature of argon gas = 28 K
Now put all the given values in the above formula, we get:


Therefore, the number of moles of argon gas is, 11.5 mol