A decrease in atomic size and an increase in nuclear charge across a period lead to
an increase in the tendency to lose electron
an increase in chemical reactivity
a decrease in electropositivity
a decrease in covalency in bond formation
Explanation
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That's not true bro...u mean elements on the left side of the periodic table are chemical inertive? Chemical reactivity doesn't increase or decrease across a period of the periodic table rather it's electropositivity and electronegativity dat decreases and increases respectively from left to right of the period of the periodic table
the ANS is C.. Atomic size or atomic radius and electropositivity are the only properties that decrease across the period.
With the above conditions, option C is correct - decrease in electropositivity across the period.
As we move across a **period** (or row) in the periodic table, the following trends occur:
1. **Atomic size (atomic radius)** decreases: This is because the **nuclear charge** (number of protons) increases, pulling the electrons closer to the nucleus. Electrons are added to the same energy level (shell), but the effective nuclear charge experienced by the outermost electrons increases.
Now let's analyze the given options:
A. **An increase in the tendency to lose electrons**: As atomic size decreases, the outermost electrons are held more tightly by the nucleus. Therefore, the tendency to lose electrons (ionization tendency) **decreases**, not increases.
B. **An increase in chemical reactivity**: Generally, smaller atoms are more reactive because their outer electrons are closer to the nucleus and are more easily involved in chemical reactions. So, the correct statement is that there is an **increase in chemical reactivity** as we move across a period.
C. **A decrease in electropositivity**: Electropositivity refers to the tendency of an atom to lose electrons and form positive ions. As mentioned earlier, the tendency to lose electrons decreases across a period due to the smaller atomic size. Therefore, the correct statement is that there is a **decrease in electropositivity**.
D. **A decrease in covalency in bond formation**: Covalency refers to the sharing of electrons between atoms in a covalent bond. Smaller atoms tend to form stronger covalent bonds because their electrons are closer to the nucleus. So, there is an **increase in covalency** as we move across a period, not a decrease.
Hence, the correct answer is **C. a decrease in electropositivity**.
The selected answer is wrong. This is because across the period the the elements become less electropositive example; Na has an oxidation number of +1 meaning it can loose an electron freely but elements like fluorine which has an oxidation number of -1 can gain an electron easily, therefore there a decrease in the ability to loose electrons and become positively charged.
Thank you.
I'm having a sick feeling for those who would ignorantly take this to be correct 
Myschool review your answers please.
These errors are becoming more frequent 
outer valency electron determines the chemical reactivity of an atom, property like metal and non ,metal is the only one determined by number of electron shell (period)
The correct option for the given question is:
A
. An increase in the tendency to lose electrons
Across a period in the periodic table, from left to right, there is a decrease in atomic size (due to the increasing effective nuclear charge) and an increase in nuclear charge (due to the increasing number of protons).
This decrease in atomic size and increase in nuclear charge lead to an increased tendency for the atoms to lose electrons, as the valence electrons are held more tightly by the stronger effective nuclear charge.
Here's an explanation for each option:
A. An increase in the tendency to lose electrons - Correct
The decreasing atomic size and increasing nuclear charge make it easier for the atoms to lose their valence electrons, increasing their tendency to form cations.
B. An increase in chemical reactivity
While the reactivity does generally increase across a period, this option is too broad and does not specifically address the effect of decreasing atomic size and increasing nuclear charge.
C. A decrease in electropositivity
Electropositivity refers to the tendency of an atom to acquire a positive charge or lose electrons. Across a period, the electropositivity actually increases due to the increasing nuclear charge and decreasing atomic size.
D. A decrease in covalency in bond formation
Covalency refers to the sharing of electrons between atoms. Across a period, the covalent character of bonds generally increases due to the increased nuclear charge and decreased atomic size, making it easier for atoms to share electrons.
Therefore, option A, "An increase in the tendency to lose electrons," is the correct answer to the given question.
