I only got 50 points (which is not 100). :-)
Look at the graph. At 80 °C, about 38 g of solute is able to dissolve, and that’s for ever 100 g of water. That means that for every 150 grams of water, 57 grams of solute can dissolve (38/2 = 19 + 38 = 57 g) at 80 °C. Since 57 g is greater than 55 g, all for he sodium chloride should dissolve in 150 g of water at 80 °C - you can put all of that into a “mathematical explanation”.
Becuz the sun refelt off the earth and on to the moon.
Molar solubility<span> is the number of moles of a substance (the solute) that can be dissolved per liter of solution before the solution becomes saturated. We calculate as follows:
</span>3Cu2+ + 2(AsO4)3-<span> = Cu3(AsO4)2
</span>
7.6 x 10^-36 = (3x^3)(2x^2)
x = 6.62 x 10^-8 M
Answer:
From least polar covalent to most polar covalent;
S-I< Br-Cl < N-H< Te-O
From most ionic to least ionic
Cs-F> Sr-Cl> Li- N> Al-O
Explanation:
Electro negativity refers to the ability of an atom in a bond to attract the shared electrons of the bond towards itself.
Electro negativity difference between two atoms is a key player in the nature of bond that exists between any two atoms. A large difference in electron negativity leads to an ionic bond while an intermediate difference in electro negativity leads to a polar covalent bond.
Based on electro negativity differences, the bonds in the answer have been arranged in order of increasing polar covalent nature or decreasing ionic nature.
Answer:
1) Ca: [Ar]4s²
2) Pm: [Xe]6s²4f⁵
Explanation:
1) Ca:
Its atomic number is 20. So it has 20 protons and 20 electrons.
Since it is in the row (period) 4 the noble gas before it is Ar, and the electron configuration is that of Argon whose atomic number is 18.
So, you have two more electrons (20 - 18 = 2) to distribute.
Those two electrons go the the orbital 4s.
Finally, the electron configuration is [Ar] 4s².
2) Pm
The atomic number of Pm is 61, so it has 61 protons and 61 electrons.
Pm is in the row (period) 6. So, the noble gas before Pm is Xe.
The atomic number of Xe is 54.
Therefore, you have to distribute 61 - 54 = 7 electrons on the orbitals 6s and 4f.
The resultant distribution for Pm is: [Xe]6s² 4f⁵.