Answer:
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Answer:
Explanation:
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In this case, according to the given chemical reaction, it possible for us to set up the expression for the calculation of the enthalpy change as shown below:
Thus, given the values of the enthalpies of formation on the attached file, we obtain:
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Explanation:
Elements that belong to same group contains same number of valence electrons. Hence, they tend to show similar chemical properties.
When we move across a period then number of electrons get added to the same shell. As a result, there will be no increase in size of elements.
Also, metals are the elements that belong to group 1, 2 and d-block elements are also known as metals. Metallic character of elements decreases when we move left to right in a periodic table.
As most reactive metals are placed on the left side of periodic table.
Since, size of elements increases on moving down the group. So, an element is able to easily lose its valence electrons because of less force of attraction between its nucleus and valence electrons.
As a result, there will be increase in reactivity of metals on moving down the group.
Thus, we can conclude that given sentences are as follows.
- Elements in the same group have the same number of valence electrons.
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Elements in the same period have the same number of electron shells.
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Metallic elements become less reactive as you move left to right in a period.
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Metallic elements become more reactive as you move top to bottom in a group.
The chemical reaction of Cavendish involving zinc would be a reaction between hydrochloric acid and zinc yielding zinc chloride and hydrogen gas. The balanced chemical equation would be:
2Zn + 2HCl = 2ZnCl + H2
This is an example of a single replacement reaction where zinc replaces hydrogen in the acid molecule.
