If a liquid containing %
(w/v) of a chemical substance is evaporated to
% of its initial volume,
then the percentage of the chemical substance in the final volume is
If ml of stock solution has to be prepared
such that ml of it when diluted to
ml will yield a ratio strength of
1: (or)
%, then the amount of the substance
required to prepare the stock solution is --- grams.
If % (w/v) concentrate of a substance should be
used in preparing ml of stock
solution, such that ml diluted to
ml will yield a
1: (or)
% strength solution, then
the quantity of the initial stock solution is --- ml.
If a solution with strength of %
(or) 1: has to be
prepared by using ml of a
1: (or)
% strength solution, then
the quantity of the diluent required is --- ml.
To prepare grams of a
substance containing % (w/w) of
an active ingredient from % (w/w) of
that substance, the quantity of the substance and diluent required are
--- grams and --- grams
respectively.
Dilution and Concentration of Solids - Method (ii)
If a moist crude drug contains
% of water and % (w/w) of active
ingredient then, the percentage (w/w) of active ingredient after drying the
crude drug will be %
Dilution and Concentration of Solids - Method (iii)
To prepare grams of
% ointment from the same oitment of
% strength then the quantity of
ointment and ointment base required are --- grams and
--- grams respectively.
Dilution and Concentration of Solids - Method (iv)
How many grams of an active ingredient should be added to
grams of a
% ointment to increase
its concentration to %
without change in the total quantity of the ointment?