Answer:
174.8 g/m is the molar mass of the solute
Explanation:
We must apply colligative property of freezing point depression.
ΔT = Kf . m . i
ΔT = T° freezing pure solvent - T° freezing solution (0° - (-2.34°C) = 2.34°C
Kf = Fussion constant for water, 1.86 °C/m
As ascorbic acid is an organic compound, we assume that is non electrolytic, so i = 1
2.34°C = 1.86°C/m . m
2.34°C / 1.86 m/°C = 1.26 m
This value means the moles of vitamin C, in 1000 g of solvent
We weighed the solute in 250 g of solvent, so let's calculate the moles of vitamin C.
1000 g ___ 1.26 moles
In 250 g ___ (250 . 1.26)/1000 = 0.314 moles
This are the moles of 55 g of ascorbic acid, so the molar mass, will be:
grams / mol ⇒ 55 g/0.314 m = 174.8 g/m
Following three <span>things when applied could make the reaction to occur more quickly;
1) Increasing Temperature:
Increase in temperature increases the Kinetic energy of molecules. This results in increase in the velocity and rate of collisions between reactants. Hence, greater the number of collisions between reactants per time greater will be the probability of formation of product per unit time.
2) Grinding Calcite:
Grinding of Calcium carbonate results in the increase of surface area of calcite. So greater the surface area greater is the exposure of Calcium carbonate to HCl molecules, hence the rate of formation of product increases.
3) Using Catalyst:
Very important. Catalyst when used decreases the activation energy and increase the rate of reaction by following methods.
a) Providing new pathway
b) weakening the bonds
c) providing surface area
d) holding up the reactant close to each other.</span>
Answer:
B. The transition of heat across matter
B. climate
this is because it influences the speed of chemical reactions in the soil
First cell theory. All living things are composed of cells.
Second cell theory. Cells are the basic unit of structure and function in living things.
Third cell theory. All cells are produced from other cells
