Answer:
12 L of 40% sulfuric acid solution and 8 L of 10% sulfuric acid solution are needed to make 20 L of sulfuric acid solution.
Explanation:
For first solution of sulfuric acid :
C₁ = 40% , V₁ = ?
For second solution of sulfuric acid :
C₂ = 10% , V₂ = ?
For the resultant solution of sulfuric acid:
C₃ = 28% , V₃ = 20L
Also,
<u>V₁ + V₂ = V₃ = 20L</u> ......................................(1)
Using
<u>C₁V₁ + C₂V₂ = C₃V₃</u>
<u>40×V₁ + 10×V₂ = 28×20</u>
So,
40V₁ + 10V₂ = 560........................................(2)
Solving 1 and 2 as:
V₂ = 20 - V₁
Applying in 2
40V₁ + 10(20 - V₁) = 560
40V₁ + 200 - 10V₁ = 560
30V₁ = 360
<u>V₁ = 12 L</u>
So,
<u>V₂ = 20 - V₁ = 8L</u>
<u><em>12 L of 40% sulfuric acid solution and 8 L of 10% sulfuric acid solution are needed to make 20 L of sulfuric acid solution.</em></u>
This is a fill in the blanks question.
This is where the blanks are: A __________ is scientific knowledge established through direct observation and remains constant. Scientific knowledge can change when scientists _____________
The answer is followiing.
Answer: A <em>law</em> is scientific knowledge established through direct observation and remains constant. Scientific knowledge can change when scientists <em>find new evidence</em>.
Explanation:
A scientific law describes the relation (usually in mathematical terms) of natural phenomena and is supported by numerous observations and experiments. The laws are established when all the observations and result show that all the facts obey the same relation. For instance, the Universal law of gravitation: all the objects are attracted with a force that is directly proportional to the product of their masses and inversely related to the square of the distance that separates them: in lay terms, everything that goes up has to go down, and you do not expect that when a parachutist jumps out of an airplane he or she does not fall on the ground.
On the other hand, a scientific theory, although is an explanation that has been repeatedly tested and verified, is always under scientific scrtutiny and, as additional evidence is gathered it can be modified or replaced by a new theory. That is why it is said that scientific theories have to be testable and falsiable: if it is not testable and falsiable then it is not a scientific theory.
Scientific theories are aimed to describe, explain and make predictions about the objectivable world.
Answer:
- Fluorine has 5 Electrons in its 2P shell
- Fluorine is so close to ideal Electron Configuration, the Electrons are held very tightly to the Nucleus.
Explanation:
Hopefully this was helpful!
Answer:
3.41 mL
Explanation:
At equivalence point from the reaction given,
Moles of 
= 2 × Moles of NaOH
Considering
Given that:
So,
