A solid with a low melting point is most likely is held together by covalent bonds. Examples are hydrocarbons, ice, sugar and sulfur. The have low melting points because of the covalent bonds . It do not form crystals therefore can easily be broken. The attractions are weak.
PH of solution at 25ºC = 8.3
![[ H_3O^+] = 10 ^{-pH}](https://tex.z-dn.net/?f=%5B%20H_3O%5E%2B%5D%20%3D%2010%20%5E%7B-pH%7D%20)
![{H_3O^+] = 10 ^{-8.3}](https://tex.z-dn.net/?f=%7BH_3O%5E%2B%5D%20%3D%2010%20%5E%7B-8.3%7D)
![[H_3O^+] = 5.011*10^{-9} M](https://tex.z-dn.net/?f=%5BH_3O%5E%2B%5D%20%3D%205.011%2A10%5E%7B-9%7D%20%20M)
hope this helps!
Answer:
2.2 x 10²² molecules.
Explanation:
- Firstly, we need to calculate the no. of moles in (6.0 g) sodium phosphate:
<em>no. of moles = mass/molar mass </em>= (6.0 g)/(163.94 g/mol) = <em>0.0366 mol.</em>
- <em>It is known that every mole of a molecule contains Avogadro's number (6.022 x 10²³) of molecules.</em>
<em />
<u><em>using cross multiplication:</em></u>
1.0 mole of sodium phosphate contains → 6.022 x 10²³ molecules.
0.0366 mole of sodium phosphate contains → ??? molecules.
<em>∴ The no. of molecules in 6.0 g of sodium phosphate</em> = (6.022 x 10²³ molecules)(0.0366 mole)/(1.0 mole) = <em>2.2 x 10²² molecules.</em>