An enclosed gas(i.e. one in a sealed container) has a volume of
$300\phantom{\rule{2pt}{0ex}}\mathrm{cm}{}^{3}$ and a temperature of
$300\phantom{\rule{2pt}{0ex}}\mathrm{K}$ . The pressure of the gas is
$50\phantom{\rule{2pt}{0ex}}\mathrm{kPa}$ . Calculate the number of moles of gas that are present in the container.
What pressure will
$3\phantom{\rule{2pt}{0ex}}\mathrm{mol}$ of gaseous nitrogen exert if it is pumped into a container that has a volume of
$25\phantom{\rule{2pt}{0ex}}\mathrm{dm}{}^{3}$ at a temperature of
$29\phantom{\rule{2pt}{0ex}}{}^{0}\phantom{\rule{2pt}{0ex}}\mathrm{C}$ ?
The volume of air inside a tyre is 19 litres and the temperature is
$290\phantom{\rule{2pt}{0ex}}\mathrm{K}$ . You check the pressure of your tyres and find that the pressure is
$190\phantom{\rule{2pt}{0ex}}\mathrm{kPa}$ . How many moles of air are present in the tyre?
Compressed carbon dioxide is contained within a gas cylinder at a pressure of 700 kPa. The temperature of the gas in the cylinder is
$310\phantom{\rule{2pt}{0ex}}\mathrm{K}$ and the number of moles of gas is
$13\phantom{\rule{2pt}{0ex}}\mathrm{mols}$ of carbon dioxide. What is the volume of the gas inside the cylinder?
Molar concentrations of liquids
A typical solution is made by dissolving some solid substance in a liquid. The amount of substance that is dissolved in a given volume of liquid is known as the
concentration of the liquid. Mathematically, concentration (C) is defined as moles of solute (n) per unit volume (V) of solution.
$$C=\frac{n}{V}$$
For this equation, the units for volume are
$\mathrm{dm}{}^{3}$ . Therefore, the unit of concentration is
$\mathrm{mol}\xb7{\mathrm{dm}}^{-3}$ .
When concentration is expressed in
$\mathrm{mol}\xb7{\mathrm{dm}}^{-3}$ it is known as the
molarity (M) of the solution. Molarity is the most common expression for concentration.
Do not confuse molarity (M) with molar mass (M). Look carefully at the question in which the M appears to determine whether it is concentration or molar mass.
Concentration
Concentration is a measure of the amount of solute that is dissolved in a given volume of liquid. It is measured in
$\mathrm{mol}\xb7{\mathrm{dm}}^{-3}$ . Another term that is used for concentration is
molarity (M)
If
$\mathrm{3,5}\phantom{\rule{2pt}{0ex}}\mathrm{g}$ of sodium hydroxide (NaOH) is dissolved in
$\mathrm{2,5}\phantom{\rule{2pt}{0ex}}{\mathrm{dm}}^{3}$ of water, what is the concentration of the solution in
$\mathrm{mol}\xb7{\mathrm{dm}}^{-3}$ ?
The concentration of the solution is
$\mathrm{0,035}\phantom{\rule{2pt}{0ex}}\mathrm{mol}\xb7{\mathrm{dm}}^{-3}$ or
$\mathrm{0,035}\phantom{\rule{2pt}{0ex}}\mathrm{M}$
You have a
$1\phantom{\rule{2pt}{0ex}}{\mathrm{dm}}^{3}$ container in which to prepare a solution of potassium permanganate (
$\mathrm{KMnO}{}_{4}$ ). What mass of
$\mathrm{KMnO}{}_{4}$ is needed to make a solution with a concentration of
$\mathrm{0,2}\phantom{\rule{2pt}{0ex}}\mathrm{M}$ ?
The mass of
$\mathrm{KMnO}{}_{4}$ that is needed is
$\mathrm{31,61}\phantom{\rule{2pt}{0ex}}\mathrm{g}$ .
How much sodium chloride (in g) will one need to prepare
$500\phantom{\rule{2pt}{0ex}}{\mathrm{cm}}^{3}$ of solution with a concentration of
$\mathrm{0,01}\phantom{\rule{2pt}{0ex}}\mathrm{M}$ ?
The mass of sodium chloride needed is
$\mathrm{0,29}\phantom{\rule{2pt}{0ex}}\mathrm{g}$
Molarity and the concentration of solutions
$\mathrm{5,95}\phantom{\rule{2pt}{0ex}}\mathrm{g}$ of potassium bromide was dissolved in
$400\phantom{\rule{2pt}{0ex}}{\mathrm{cm}}^{3}$ of water. Calculate its molarity.
$100\phantom{\rule{2pt}{0ex}}\mathrm{g}$ of sodium chloride (NaCl) is dissolved in
$450\phantom{\rule{2pt}{0ex}}{\mathrm{cm}}^{3}$ of water.
How many moles of NaCl are present in solution?
What is the volume of water (in
${\mathrm{dm}}^{3}$ )?
Calculate the concentration of the solution.
What mass of sodium chloride would need to be added for the concentration to become
$\mathrm{5,7}\phantom{\rule{2pt}{0ex}}\mathrm{mol}\xb7{\mathrm{dm}}^{-3}$ ?
What is the molarity of the solution formed by dissolving
$80\phantom{\rule{2pt}{0ex}}\mathrm{g}$ of sodium hydroxide (
$\mathrm{NaOH}$ ) in
$500\phantom{\rule{2pt}{0ex}}{\mathrm{cm}}^{3}$ of water?
What mass (g) of hydrogen chloride (
$\mathrm{HCl}$ ) is needed to make up
$1000\phantom{\rule{2pt}{0ex}}{\mathrm{cm}}^{3}$ of a solution of concentration
$1\phantom{\rule{2pt}{0ex}}\mathrm{mol}\xb7{\mathrm{dm}}^{-3}$ ?
How many moles of
$\mathrm{H}{}_{2}\mathrm{SO}{}_{4}$ are there in
$250\phantom{\rule{2pt}{0ex}}{\mathrm{cm}}^{3}$ of a
$\mathrm{0,8}\phantom{\rule{2pt}{0ex}}\mathrm{M}$ sulphuric acid solution? What mass of acid is in this solution?
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest.
Rafiq
Rafiq
what is differents between GO and RGO?
Mahi
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.?
How this robot is carried to required site of body cell.?
what will be the carrier material and how can be detected that correct delivery of drug is done
Rafiq
Rafiq
if virus is killing to make ARTIFICIAL DNA OF GRAPHENE FOR KILLED THE VIRUS .THIS IS OUR ASSUMPTION
Anam
analytical skills graphene is prepared to kill any type viruses .
Anam
Any one who tell me about Preparation and application of Nanomaterial for drug Delivery
The nanotechnology is as new science, to scale nanometric
brayan
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Damian
Is there any normative that regulates the use of silver nanoparticles?