Answer:
The classification and illustrations are attached in the drawing.
Explanation:
It is possible to identify the pure substance observing the figure, since it is the only one that has 2 joined atoms (purple and blue) which forms a single compound.
On the other hand, the homogeneous mixture is identified by noting that its atoms are more united with respect to the heterogeneous mixture, highlighting that in homogenous mixtures the atoms, elements or substances are not visible to the naked eye and are in a single phase, instead in the heterogeneous mixture if they can be differentiated.
Answer:

Explanation:
Hello,
In this case, for the given reactants we identify the following chemical reaction:

Thus, we evidence a 1:1 molar ratio between KOH and HCl, therefore, for the complete neutralization we have equal number of moles, that in terms of molarities and volumes become:

Hence, we compute the volume of HCl as shown below:

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Answer:
It is calcium phosphide.
Explanation:
Calcium phosphide is a salt like material that is composed of calcium and phosphorus in the ratio of 2:5. It has the appearance of red brown Crystalline salt.
It is use as rodenticide to kill rats.
It is also use in fire works.