Quick questions on Soaps and detergents explained: structure, saponification and cleaning action for HSC Chemistry Module 7

4short Q&A pairs drawn directly from our worked dot-point answer. For full context and worked exam questions, read the parent dot-point page.

What are vague hard-water explanations?

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"Soap does not work well in hard water" without naming

Ca^{2+}

Mg^{2+}

and the insoluble precipitate formed will not earn full marks.

What is q1?

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State the reagent, condition, and both products of saponification of a triglyceride fat. [3 marks]

What is q2?

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A student saponifies 20.2 g of tripalmitin (

M = 807.3\ \text{g mol}^{-1}

) with excess NaOH. Calculate the theoretical mass of sodium palmitate (

M = 278.4\ \text{g mol}^{-1}

) produced, to 3 significant figures. [3 marks]

What is q3?

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Explain why a synthetic sulfonate detergent continues to clean effectively in hard water while soap forms a scum. [4 marks]

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