Answer with Explanation:
"Mass" and "weight" should never be used interchangeably with each other. Mass refers to the <u>total amount of matter</u><u> that can be measured in an object, </u>while weight refers to the<u> measure of the</u><u> force of gravity</u><u> that is acting on the object's mass.</u>
The mass of an object is<u> constant</u> (meaning, it doesn't change even if the object will be placed on another location) while the weight of an object relies on the <em>force of gravity.</em> So, this means that your mass on Earth and on the moon are identical, however, your weight on Earth and on the Moon are different. You will weigh lesser on the Moon because it has a lesser surface gravity than that of Earth.
So, this explains the answer.
Answer:

Explanation:
= Concentration of stock solution
= Concentration of solution
= Volume of stock solution = 19 mL
= Volume of solution = 0.31 L= 310 mL
We have the relation


The concentration of the diluted solution will be 0.613 times the concentration of the stock solution.
Take a hypothetical sample of exactly 100 grams of the solution.
(16g urea) / (60.06 g urea/mol) = 0.2664 mol urea
((100 g total) - (16g urea)) = 84.0 g H2O = 0.0840 kg H2O
(0.2664 mol) /0.0840 (kg) = 3.17143mol/kg = 3.18m urea
A physical change is like freezing water and it turns into Ice.
In chemistry, there are two types of change, they are chemical and physical changes. A chemical change is one in which new substance are formed and it is always irreversible while a physical change is one in which no new substance is formed and it is always reversible. There are many factors that can indicate that a chemical change has taken place, these include: energy transfer, formation of precipitation, gas production, etc. Fracture formation does not indicate chemical change. In fracture formation nothing changes, so it is a form of physical change.