Since you forgot to include the choices for classification, I would just define each of these and tell you the hints that would help you classify them.
Among these acids and bases, its is the strong acids and strong bases that are easily classified. You should note that there are only 7 strong acids existing. All the rest are weak acids. These 7 acids are: HCl, HBr, HI, HClO₃, HClO₄, HNO₃ and H₂SO₄. On the other hand, there are only 8 strong bases; the rest are weak bases. These are the hydroxides of the Group ! and !! metals: LiOH, NaOH, KOH, RbOH, CsOH, Ca(OH)₂, Sr(OH)₂, and Br(OH)₂.
For the weak acids and weak bases, just remember the definitions of Arrhenius, Lewis and Bronsted-Lowry. A weak base are those compounds that accept H⁺ protons, produce OH⁻ ions when solvated and an electron donor. A weak acid are those compounds that donate H⁺ protons, produce H⁺ ions when solvated and an electron acceptor.
Answer:
- 0.99 °C ≅ - 1.0 °C.
Explanation:
- We can solve this problem using the relation:
<em>ΔTf = (Kf)(m),</em>
where, ΔTf is the depression in the freezing point.
Kf is the molal freezing point depression constant of water = -1.86 °C/m,
m is the molality of the solution (m = moles of solute / kg of solvent = (23.5 g / 180.156 g/mol)/(0.245 kg) = 0.53 m.
<em>∴ ΔTf = (Kf)(m)</em> = (-1.86 °C/m)(0.53 m) =<em> - 0.99 °C ≅ - 1.0 °C.</em>
The correct answer among the choices listed above is option D. The average kinetic energy of water molecules as water freeze <span>decreases as water releases energy to its surroundings. Energy is released as the molecules go into a more condensed phase which is the solid.</span>
0.091 moles are contained in 2.0 L of N2 at standard temperature and pressure.
Explanation:
Data given:
volume of the nitrogen gas = 2 litres
Standard temperature = 273 K
Standard pressure = 1 atm
number of moles =?
R (gas constant) = 0.08201 L atm/mole K
Assuming nitrogen to be an ideal gas at STP, we will use Ideal Gas law
PV = nRT
rearranging the equation to calculate number of moles:
PV = nRT
n = 
putting the values in the equation:
n = 
n = 0.091 moles
0.091 moles of nitrogen gas is contained in a container at STP.
