Option 2nd - a mixture of solid particles in a liquid.
<h2>Explanation:
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For a Mixture of two immiscible liquids (for example water and oil) it is not possible to filter them with a filter as both of the liquid will pass through it.
For a mixture of a solid and a liquid (for example sand and water) it can be easily separated through a filter as on filtration solid will be left on the filter and the liquid will pass through it.
For a mixture of two miscible liquids (for example milk and water) both of them will form a single identity, and on filtration both of them will pass through the filter. Hence it is not possible to separate them through filter.
For a mixture of liquid and gas (for example drinking soda or Pepsi) filter is not needed for their separation as it will be separated when exposed in air.
In (NH4)2C2O4 there are four moles of Hydrogen in the compound (NH4), but there two molecules of (NH4) in this compound. That's what the 2 in (NH4)2 means, so multiply 4 x 2 = 8.
The electrons are lost from the valence shell (outermost electron shell) of the atom.
Explanation:
This is able to be inferred not only because valence electrons being lost first is a trend but also because the atom in question has actually 3 valence electrons (13-2-8 = 3).
