Answer : The mass of calcium chloride (in g) needed is, 1.92 grams.
Explanation : Given,
Boiling point of elevation constant 
for water = 
Mass of water (solvent) = 
Molar mass of 
= 110.98 g/mole
Formula used :
where,
= change in boiling point = 
i = Van't Hoff factor = 3 (for electrolyte)
= boiling point constant for water
m = molality
Now put all the given values in this formula, we get
Therefore, the mass of calcium chloride (in g) needed is, 1.92 grams.
When you encounter a storm drain, gravel surface or pothole.
Answer:
As per the general rule for finding oxidation number, When H is bonded with non-metal it has oxidation number as 1. As in the given ion, hydrogen is bonded with non-metal oxygen and there are three hydrogen atom, the oxidation number of hydrogen atom is 3.
Answer:
A
Explanation:
A. is correct
A chemical change is one in which a new substance is formed. To check if there is a chemical change when the two liquids were combined, what we simply need to do is to see if there is the formation of a new substance. The new substance formed is expected to be chemically and physically distinctive from its formative members.
B is incorrect
Being pure or impure does not provide any information if a chemical change had occurred or not.
C is incorrect
The toxicity of both doesn’t provide any information as regards if a chemical change had occurred or not
D is incorrect.
