Use of amount of substance in relation to masses of pure substances

Easy

An agricultural scientist analyzed the concentration of dissolved fertilizer salts in a drainage runoff sample.

The scientist used the following procedure:

Filter the runoff water sample to remove suspended soil particles.
Measure the mass of a clean, dry porcelain crucible.
Pipette exactly $cm340\text{ cm}^3$ of the filtered runoff water into the crucible.
Heat the crucible gently until all the water has evaporated to dryness.
Measure the mass of the crucible and the dry residue.

The results of the experiment are recorded in the table below:

Measurement	Mass (g)
Empty crucible	$28.452$
Crucible and dry residue	$28.524$

Calculate the concentration of dissolved fertilizer salts in this runoff sample, in $dm−3\text{g dm}^{-3}$ .

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Use of amount of substance in relation to masses of pure substances Questions