138 DIY Science: Illustrated Guide to Home Chemistry Experiments
FIGURE 7-3: Bringing the solution level in the volumetric
flask just up to the index line
oALIpToN ACTIvITIES
If you have time and the required materials, consider
performing these optional activities:- Make up 100 mL each of 1 M bench solutions of
sulfuric acid, nitric acid, and aqueous ammonia. - Look up values for the mass percentage and density
of aqueous solutions of hydrochloric acid at various
concentrations. Graph those values to determine
whether the relationship is linear. Do the same for
sulfuric acid.
RQEWEvI UESTIOnS
q 1 : You need to make up 100 mL of 3 M nitric acid. The concentrated nitric acid you have on hand lists its mass percentage as 68%.
Is this sufficient information for you to make up the 3 M bench solution? If not, why? If so, how much concentrated nitric acid would
you dilute to make 100 mL of 3 M nitric acid?
dR. mARy CHERvENAk CommENTS:
Sulfuric and nitric acid solutions may require the donning
of chemically impervious aprons. They eat through
clothing, including lab coats. Even dilute solutions can ruin
clothes (lots of tiny holes). I would recommend washing
anything worn during this experiment separately from
all other clothes. (Personal experience: in grad school,
everything I owned was full of tiny holes.)