Best Answer
C) is the best description, although a scientific theory is not necessarily a "fact". They are, however, based on evidence.
A) is complete garbage.
B) is a good description of a scientific "law"- something that predicts how a certain event will occur without explaining why this is (for instance, the law of gravity accurately describes the gravitational forces between two bodies, but does not explain why these forces are there).
D) is a scientific "hypothesis"- an explanation for an observed phenomena that is yet to be proven.
To determine the volume of both concentration of vinegar, we need to set up two equations since we have two unknowns.
For the first equation, we do a mass balance:
mass of 100% vinegar + mass of 13% vinegar = mass of 42% vinegar
Assuming they have the same densities, then we can write this equation in terms of volume.
V(100%) + V(13%) = V(42%)
we let x = V(100%)
y = V(13%)
x + y = 150
For the second equation, we do a component balance:
1.00x + .13y = 150(.42)
x + .13y = 63
The two equations are
x + y = 150
x + .13y = 63
Solving for x and y,
x = 50
y = 100
Therefore, you need to mix 50 mL of the 100% vinegar and 100 mL of the 13% vinegar.
D! because when you record something you will probably analyze the results and those are two big KEY components of an Experiment! <span />
Answer:
Explanation:
From the statement of the problem,
B₂S₃
+ H₂O
→ H₃BO₃
+ H₂S
B₂S₃ + H₂O → H₃BO₃ + H₂S
We that the above expression does not conform with the law of conservation of mass:
To obey the law, we need to derive a balanced reaction equation:
Let us use the mathematical method to obtain a balanced equation.
let the balanced equation be:
aB₂S₃ + bH₂O → cH₃BO₃ + dH₂S
where a, b, c and d will make the equation balanced.
Conservating B: 2a = c
S: 3a = d
H: 2b = 3c + 2d
O: b = 3c
if a = 1,
c = 2,
b = 6,
2d = 2(6) - 3(2) = 6, d = 3
Now we can input this into our equation:
B₂S₃ + 6H₂O → 2H₃BO₃ + 3H₂S
B₂S₃
+ 6H₂O
→ 2H₃BO₃
+ 3H₂S