Question

19.
the elements in group 7a (group 17) of the periodic table are called the

a) halogens.

b) alkali metals.

c) alkaline earth metals.

d) noble gases.

Explanation:

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<reasoning>

Identify the periodic table group name

Group 17 (7A) elements: fluorine (F), chlorine (Cl), bromine (Br), iodine (I), and astatine (At).

Match group with options

• Group 17 (7A) = halogens
• Group 1 = alkali metals
• Group 2 = alkaline earth metals
• Group 18 = noble gases

</reasoning>

<answer>
<mcq-correct>(A) halogens.</mcq-correct>
<mcq-option>(B) alkali metals.</mcq-option>
<mcq-option>(C) alkaline earth metals.</mcq-option>
<mcq-option>(D) noble gases.</mcq-option>
</answer>

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Answer:

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</pre_analysis>

<reasoning>

Identify the periodic table group name

Group 17 (7A) elements: fluorine (F), chlorine (Cl), bromine (Br), iodine (I), and astatine (At).

Match group with options

• Group 17 (7A) = halogens
• Group 1 = alkali metals
• Group 2 = alkaline earth metals
• Group 18 = noble gases

</reasoning>

<answer>
<mcq-correct>(A) halogens.</mcq-correct>
<mcq-option>(B) alkali metals.</mcq-option>
<mcq-option>(C) alkaline earth metals.</mcq-option>
<mcq-option>(D) noble gases.</mcq-option>
</answer>

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