
- <em>Expansion </em><em>of </em><em>particles</em><em> </em><em>of</em><em> </em><em>substances.</em><em> </em>
- <em>Increase</em><em> </em><em>in </em><em>temperature</em><em>.</em>
- <em>Change</em><em> </em><em>in </em><em>state</em><em>.</em>
- <em>Change</em><em> </em><em>in </em><em>physical</em><em> </em><em>property</em>
- <em>It </em><em>may </em><em>bring</em><em> </em><em>out </em><em>chemical</em><em> </em><em>changes</em><em>.</em>
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Answer:
Alkali metals are soft and have low melting points.
<h2>see in the attachment hope it helps you</h2>
Answer:
The compound which are boh soluble in water and hexane is
B. Ethanol and 1-propanol
Explanation:
The compounds ethanol and 1-propanol are soluble in both hexane and water.
It is soluble in water as both consists of polar end due to hydrogen bonding present in the -OH functional group.
and both are soluble in hexane as they contain a non polar end and the alliphatic hydrocarbon chain in them.
The solubility of alcohols varies in increasing order as the hydrocarbon chain increases. And becaue of this it becomes more non polar.
Non polar properties decreases for branched molecules.
so, the correct option is ethanol and 1-propanol.
<span>PbO
Let's look at each of the 4 compounds and see what's needed.
PbO.
* Oxygen has a valance shell that's missing 2 electrons and wants to get those 2 elections. Lead donates them, so you have a Lead (II) ions. This is a correct choice.
PbCl4
* Chlorine wants to grab 1 electron to fill it's valance shell and Lead donates that election. However, there's 4 chlorine atoms and every one of them wants and electron, and lead is donating all 4 of the desired electrons making the Lead (IV) ion. So this is a bad choice.
Pb2O
* Oxygen still wants 2 electrons and gets them from the lead. But there's 2 lead atoms and each of them donates 1 election making for 2 Lead(I) ions. So this too is a bad choice.
Pb2S
* Sulfur is in the same column of the periodic table as oxygen and if this compound were to exist would have similar properties as Pb2O and would have Lead(I) ions. So this is a bad choice.</span>