Answer:
0.85 mole
Explanation:
Step 1:
The balanced equation for the reaction of CaCl2 to produce CaCO3. This is illustrated below:
When CaCl2 react with Na2CO3, CaCO3 is produced according to the balanced equation:
CaCl2 + Na2CO3 -> CaCO3 + 2NaCl
Step 2:
Conversion of 85g of CaCO3 to mole. This is illustrated below:
Molar Mass of CaCO3 = 40 + 12 + (16x3) = 40 + 12 + 48 = 100g/mol
Mass of CaCO3 = 85g
Moles of CaCO3 =?
Number of mole = Mass /Molar Mass
Mole of CaCO3 = 85/100
Mole of caco= 0.85 mole
Step 3:
Determination of the number of mole of CaCl2 needed to produce 85g (i.e 0. 85 mole) of CaCO3.
This is illustrated below :
From the balanced equation above,
1 mole of CaCl2 reacted to produced 1 mole of CaCO3.
Therefore, 0.85 mole of CaCl2 will also react to produce 0.85 mole of CaCO3.
From the calculations made above, 0.85 mole of CaCl2 is needed to produce 85g of CaCO3
It takes so much heat to melt ice or evaporate water because extra energy is required to break the hydrogen bonds between water molecules.
<h3>
Hydrogen bond</h3>
Hydrogen bonding is an electrostatic force of attraction between a hydrogen atom found between a pair of other atoms having a high affinity for electrons.
Hydrogen bonds cause water to be exceptionally attracted to each other creating cohesion.
It takes so much heat to melt ice or evaporate water because extra energy is required to break the hydrogen bonds between water molecules.
Find out more on Hydrogen bond at: brainly.com/question/12798212
Answer:
A. Both freezing and melting are physical changes.
Explanation:
Even if you were to freeze water, the molecules are still water molecules, and vise versa with melting it.
Answer:
Crystallization is the solidification of atoms or molecules into a highly structured form called a crystal.
Explanation:
Organic chemistry is the scientific study of the structure, properties, composition, reactions, and synthesis of organic compounds
<span> UV radiation are high energy radiations and they are mutation causing agents so
</span>Mutagen <span> best describes the relationship of solar UV radiation to the environment
so option A is correct
hope it helps</span>