The three factors determine the chemical properties of an element:
<span><span>The number and arrangement of electrons in an atom
</span><span>The number of valence electrons
</span><span>The number and arrangement of electrons</span></span>
When in water, MgCl2 dissociates into magnesium ions and Cl- ions and NaOH into Na and OH ions. The equation is as follows:
MgCl2 = Mg2+ + 2Cl-
NaOH = Na+ + OH-
The initial concentrations are as follows:
[Mg2+] = .220(<span> 2.47x10^-4) / .220+.180 = 1.36x10^-4 M Mg2+
</span>[OH-] = .180 (3.52x10^-4) / .220+.180 = 1.58x10^-4 M OH-
Characteristic properties are used because the sample size and the shape of the substance does not matter.
4. A
because PbCl2 is an ionic compound and it's solid, so it's a substance.
It cannot be mixture, because it's a pure molecule.
5. D
despite that both substances are gases, colorless they are different molecules, so they should have different either chemical and physical properties
6. C
this substance made from W atoms and others are made from molecules
