Answer:
2.7 °C.kg/mol
Explanation:
Step 1: Calculate the freezing point depression (ΔT)
The normal freezing point of a certain liquid X is-7.30°C and the solution freezes at -9.9°C instead. The freezing point depression is:
ΔT = -7.30 °C - (-9.9 °C) = 2.6 °C
Step 2: Calculate the molality of the solution (b)
We will use the following expression.
b = mass of solute / molar mass of solute × kilograms of solvent
b = 102. g / (162.2 g/mol) × 0.650 kg = 0.967 mol/kg
Step 3: Calculate the molal freezing point depression constant Kf of X
Freezing point depression is a colligative property. It can be calculated using the following expression.
ΔT = Kf × b
Kf = ΔT / b
Kf = 2.6 °C / (0.967 mol/kg) = 2.7 °C.kg/mol
Answer:
See below :)
Explanation:
There is an evident reason why some of the solutions Carson's has listed and observed, does conduct electricity and some that do.
A flow of electrical charge is called an electric current. Ions are atoms, or sets of atoms, that contain an electrical charge. There are two types of ions, cation or a positively charged ion containing a deficiency of electrons, and anion or a negatively charged ion which contains a surplus of electrons. When a solution conducts electricity the charge is carried within by ions that move through the solution. The larger the number of ions in the solution, the better the conductivity of the solution is. Pure water does not conduct very well because it contains very few ions, but when table salt (NaCl) is dissolved in the water, this solution does conduct well because the solution contains a more abundance of ions. The majority of the ions come from the table salt, chemically names sodium chloride. Because Sodium contains its sodium ions, and these are positive charge and chloride ions which is a negative charge, it is called an ionic substance. Not every substance is made up of ions, one such example is sugar (C12H22O11). Sugar is made up of uncharged particles also called molecules. Although sugar is a substance its molecules do not hold a charge, thus when sugar is dissolved in water, the solution does not conduct electricity, due to the lack of ions in the solution.
Therefore, depending on the ions that make up the compound, the substance would or would not conduct electricity.
Substances that exist in solution almost completely as ions are called strong electrolytes. Therefore, the answer is C.
Answer:
cell
chloroplast and cell wall
nucleus
life processes
cell membrane
shape and size
vacuole
Hope it helps
Explanation:
Let the age to be found in years is y.
Hence,
= (\frac{1}{2})^{\frac{y}{5730yr}}
Solve for y as follows.
0.53913 = (\frac{1}{2})^{\frac{y}{5730yr}}
Now, taking log on both the sides as follows
log 0.53913 = 
=
z = 
= 5107 years
Thus, we can conclude that the time since death is 5107 years.