Answer:
The correct answer is "Temperature is a measure of the average kinetic energy of the molecules in a substance".
Explanation:
The kinetic energy of a substance is defined as the power that results from the movement of its particles. In this sense, temperature could be defined as a measure of the average kinetic energy of the molecules in a substance. Actually, temperature expressed in Kelvin degrees is directly proportional to the average of the kinetic energy. On the other hand, heat is defined as the total energy in a substance.
In 1 mol of CH3OH, you have 4 H-atoms (because 3 H-atoms
are attached to the C-atom, and one H-atom in the OH group). That means
in 0.500 mol of CH3OH, you have 2 H-atoms since it is halved. And then we have Avogadro's constant: 6.02 * 1023.
The question asks for how many hydrogen atoms there are in 0.500 mol CH3OH. Using the numbers that we have (Avogadro's constant and no. of H-atoms), the answer of the question will be something like:
<span>H-atoms in CH3OH = 2 * 6.02 * </span>1023<span> = ~1.2 * 10</span>24
Answer:
D. I < III < II
Explanation:
- The osmotic pressure (π) is given by the relation:
<em>π = iMRT.</em>
where, π is the osmotic pressure.
i is van 't Hoff factor.
M is the molarity of the solution.
R is the general gas constant.
T is the temperature.
<em>M, R and T are constant for all solutions.</em>
So, the osmotic pressure depends on the van 't Hoff factor.
- The van 't Hoff factor is the ratio between the actual concentration of particles produced when the substance is dissolved and the concentration of a substance as calculated from its mass.
- For most non-electrolytes dissolved in water, the van 't Hoff factor is essentially 1.
- For most ionic compounds dissolved in water, the van 't Hoff factor is equal to the number of discrete ions in a formula unit of the substance.
For C₂H₆O₂ (non-electrolyte solute): i = 1.
For MgCl₂: i = 3.
It dissociates to give (Mg²⁺ + 2Cl⁻).
For NaCl: i = 2.
It dissociates to give (Na⁺ + Cl⁻).
So, the solute that has the highest osmotic pressure is II. 0.15 M MgCl₂, then III. 0.15 M NaCl, then I. 0.15 M C₂H₆O₂.
<em>D. I < III < II.</em>
<em></em>
light-colored, silica-rich igneous rock that is less dense than basaltic rock. dense, dark-colored igneous rock formed from magma;rich in magnesium and iron and poor in silica. Describes magma or igneous rock that is rich in feldspars and silica and that is generally light in color.
