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3 marksCore biology3.1.1

The relative molecular mass (

M_\mathrm{r}

) of

\alpha

-glucose is 180 and of water is 18. Six

\alpha

-glucose molecules are joined in one unbranched chain.

(a)

Calculate the

M_\mathrm{r}

of the chain.

[2 marks]

WorkingFinal answer

(b)

Explain why the

M_\mathrm{r}

of the chain is less than the total

M_\mathrm{r}

of the separate glucose molecules.

[1 mark]

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