In science it is best to continue research, and rinse and repeat. This allows for a stronger hypothesis if you're results are the same every time, or change your hypothesis if you stumble upon new results. <span />
Answer:
The correct answer is 0.0033 L (33.0 mL)
Explanation:
We uses the Charles's law which describes the changes in the volume (V) of a gas and its temperature in Kelvin (T) at constant pressure. The mathematical expression is the following:
V₁/T₁ = V₂/T₂
We have the following data:
V₁= 31.0 mL = 0.0031 L
T₁= 19.0°C = 292 K
T₂= 38.0°C = 311 K
V₂= ?
We calculate V₂ from the mathematical expression, as follows:
V₂= V₁/T₁ x T₂ = 0.0031 L/(292 K) x 311 K = 0.0033 L
Answer:
pH = 12.15
Explanation:
To determine the pH of the HCl and KOH mixture, we need to know that the reaction is a neutralization type.
HCl + KOH → H₂O + KCl
We need to determine the moles of each compound
M = mmol / V (mL) → 30 mL . 0.10 M = 3 mmoles of HCl
M = mmol / V (mL) → 40 mL . 0.10 M = 4 mmoles of KOH
The base is in excess, so the HCl will completely react and we would produce the same mmoles of KCl
HCl + KOH → H₂O + KCl
3 m 4 m -
1 m 3 m
As the KCl is a neutral salt, it does not have any effect on the pH, so the pH will be affected, by the strong base.
1 mmol of KOH has 1 mmol of OH⁻, so the [OH⁻] will be 1 mmol / Tot volume
[OH⁻] 1 mmol / 70 mL = 0.014285 M
- log [OH⁻] = 1.85 → pH = 14 - pOH → 14 - 1.85 = 12.15
The answer is liter hope this helped :)
Answer:
There is too much waste involved in the process. Cold fusion experiments have been conducted at room temperature only. The process does not produce enough energy to meet the needs of modern humans.