Texas Instruments Calculators
Hewlett Packard Calculators
Units Conversion Lookup
Linear Least Squares Regression
Newton's Method Equation Solver
Another Problem 1
In an experiment, a chemist allows a red solution to flow at a rate of 0.1
mL per second for 14 seconds into a beaker containing a blue solution.
The red solution has a density of 1.10 g/mL, and the blue solution has
a density of 0.98 g/mL. Rounding each answer to the correct number of
significant figures, if there are initially 20. mL of blue solution in
- How many grams of blue solution are in the beaker?
- How many milliliters of red solution have been added after 14 seconds?
- How many grams of red solution have been added after 14 seconds?
- Recalculate the answers for (b) and (c) for a red
flow rate of 0.10 mL per second.
(a) 20 g (b) 1 mL (c) 2 g (d) 1.4 mL, 1.5 g
This is largely a problem of unit conversions and keeping track of
significant figures. For a flow rate of 0.1 ml per second, there is
only 1 significant figure for this measurement, so the answers that use
this quantity are only good to 1 significant figure.
- 20. mL x .98 g/mL = 19.6 g, but to 2 sig figs, this is rounded to 20. g.
- 0.1 mL/s x 14 s = 1.4 mL, so to 1 sig fig this is rounded down to 1 mL.
- 0.1 mL/s x 14 s x 1.10 g/mL = 1.54 g, so to 1 sig fig this is rounded
up to 2 g.
- 0.10 mL/s x 14 s = 1.4 mL, so to 2 sig fig this is 1.4 mL
0.10 mL/s x 14 s x 1.10 g/mL = 1.54 g, so to 2 sig fig this is rounded
down to 1.5 g.
Try another problem like this one.
Next Try It Out Problem.