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Class 10 Chemistry (India)

Lesson 5: Displacement and double displacement reactions

Displacement and double displacement reactions

Pirate captain Jack Sparrow maintains a chemistry laboratory aboard his ship to keep his weapons game strong.

One day he accidentally drops his stock of sodium (start text, N, a, end text) in the water and observes a violent reaction.

\begin{aligned} \text{Na}(\text{s})+\text{H}_2\text O(\text l)\xrightarrow{\text{boom!}}\fbox{?} \end{aligned}

Which of the following reactions does Captain Sparrow observe?
Note: start text, N, a, end text is more reactive than start text, H, end text.

(Choice A)
$\begin{aligned} 2\text{Na}(\text s)+2\text{H}_2\text O(\text{l})\rightarrow2\text{NaOH}(\text{aq})+\text H_2(\text g) \end{aligned}$
(Choice B)
$\begin{aligned} 2\text{Na}(\text s)+\text{H}_2\text O(\text{l})\rightarrow\text{Na}_2\text O(\text{aq})+\text H_2(\text g) \end{aligned}$
(Choice C)
$\begin{aligned} \text{Na}(\text s)+2\text{H}_2\text O(\text{l})\rightarrow\text{Na}(\text{s})+\text O_2(\text g)+2\text H_2(\text g) \end{aligned}$
(Choice D)
$\begin{aligned} \text{Na}(\text s)+\text{H}_2\text O(\text{l})\rightarrow\text{NaOH}_2(\text{aq}) \end{aligned}$

Stuck?