Convert mole to gram by multiplying the molar mass of sodium
0.500mol Na x 22.990g = 11.495g of Na
Colligative properties are those substances that depend
on the number of substances in the solution, not in the identity of that
substance. The property changes the way that it does when the amount of solute
is increased because it enables the solute to be scattered more. For example,
the freezing point of salt water is lower than that of the pure water due to
the salt ions present in water.
Answer:
The biological significance is that it is the normal human body temperature and also the optimum temperature of the enzyme.
Explanation:
- Enzymes are biological catalysts that speed up the rate of chemical reactions.
- Enzymes catalyze specific reactions by working on a specific substrate to convert it into a product.
- The rate of enzyme activity depends on several factors which include pH, temperature, substrate concentration, and enzyme concentration among others.
- Enzymes work best at a specific pH and temperature known as optimum pH and optimum temperature respectively.
- In this case, enzyme amylase works best at a temperature of 37° C which is equivalent to the normal human body temperature.
Light energy into chemical energy
Answer : The molecular weight of a substance is 157.3 g/mol
Explanation :
As we are given that 7 % by weight that means 7 grams of solute present in 100 grams of solution.
Mass of solute = 7 g
Mass of solution = 100 g
Mass of solvent = 100 - 7 = 93 g
Formula used :

where,
= change in freezing point
= temperature of pure water = 
= temperature of solution = 
= freezing point constant of water = 
m = molality
Now put all the given values in this formula, we get


Therefore, the molecular weight of a substance is 157.3 g/mol