Question

select all the correct answers.

which two molecules are compounds?

\\(\text{nahco}_3\\)

\\(\text{o}_3\\)

\\(\text{cl}_2\\)

\\(\text{c}_8\text{h}_{18}\\)

Explanation:

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<reasoning>

Definir compuestos y elementos

Using the Elements and Compounds and Molecular Classification knowledge points
\[
\text{Compuesto} = \text{Sustancia formada por dos o más elementos químicos diferentes combinados químicamente.}
\]
\[
\text{Elemento} = \text{Sustancia formada por un solo tipo de átomo.}
\]

Analizar cada opción dada

Using the Elements and Compounds and Molecular Classification knowledge points
\[

$$\begin{aligned} &\text{1. } \mathrm{NaHCO_3} \implies \text{Contiene Na, H, C, O (4 elementos diferentes) } \therefore \text{Es un compuesto.} \\ &\text{2. } \mathrm{O_3} \implies \text{Contiene solo oxígeno (1 elemento) } \therefore \text{Es un elemento molecular.} \\ &\text{3. } \mathrm{Cl_2} \implies \text{Contiene solo cloro (1 elemento) } \dots \text{Es un elemento molecular.} \\ &\text{4. } \mathrm{C_8H_{18}} \implies \text{Contiene C y H (2 elementos diferentes) } \therefore \text{Es un compuesto.} \end{aligned}$$

\]
</reasoning>

<answer>
<mcq-correct>(A) \(\text{NaHCO}_3\)</mcq-correct>
<mcq-option>(B) \(\text{O}_3\)</mcq-option>
<mcq-option>(C) \(\text{Cl}_2\)</mcq-option>
<mcq-correct>(D) \(\text{C}_8\text{H}_{18}\)</mcq-correct>
</answer>

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Answer:

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<reasoning>

Definir compuestos y elementos

Using the Elements and Compounds and Molecular Classification knowledge points
\[
\text{Compuesto} = \text{Sustancia formada por dos o más elementos químicos diferentes combinados químicamente.}
\]
\[
\text{Elemento} = \text{Sustancia formada por un solo tipo de átomo.}
\]

Analizar cada opción dada

Using the Elements and Compounds and Molecular Classification knowledge points
\[

$$\begin{aligned} &\text{1. } \mathrm{NaHCO_3} \implies \text{Contiene Na, H, C, O (4 elementos diferentes) } \therefore \text{Es un compuesto.} \\ &\text{2. } \mathrm{O_3} \implies \text{Contiene solo oxígeno (1 elemento) } \therefore \text{Es un elemento molecular.} \\ &\text{3. } \mathrm{Cl_2} \implies \text{Contiene solo cloro (1 elemento) } \dots \text{Es un elemento molecular.} \\ &\text{4. } \mathrm{C_8H_{18}} \implies \text{Contiene C y H (2 elementos diferentes) } \therefore \text{Es un compuesto.} \end{aligned}$$

\]
</reasoning>

<answer>
<mcq-correct>(A) \(\text{NaHCO}_3\)</mcq-correct>
<mcq-option>(B) \(\text{O}_3\)</mcq-option>
<mcq-option>(C) \(\text{Cl}_2\)</mcq-option>
<mcq-correct>(D) \(\text{C}_8\text{H}_{18}\)</mcq-correct>
</answer>

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