Hygroscopic nature of NaOH is the main reason for the lower concentration of the sodium hydroxide in the solution.
<u>Explanation:</u>
- It is a well known fact that Sodium hydroxide pellets are hygroscopic in nature, which clearly means that the sodium hydroxide pellets absorbs moisture from the air, so that it becomes deliquescent.
- When the NaOH crystals are weighed, the crystals absorb moisture from the surroundings, and so the weight of the crystals may change, so the concentration of the solution was lower than the required one.So it is not possible to prepare NaOH solution under normal room temperature.
- So, while preparing the solution of NaOH we have to be more careful.
Answer:
The piston will move down
Explanation:
We can solve this problem by using Charle's Law, which states that:
"For a fixed mass of an ideal gas kept at constant pressure, the volume of the gas is directly proportional to the absolute temperature of the gas"
Mathematically:
where
V is the volume of the gas
T is the absolute temperature of the gas
In this problem, we have a gas placed in a container with a moveable piston. We are also told that the gas is kept at constant pressure, so we can apply Charle's Law.
We are told that the gas is cooled down: this means that its absolute temperature decreases. Therefore, according to Charle's Law, this means that the volume of the gas also decreases: therefore, the piston of the container will move down.
Before I get to the answer, I would recommend that you post biology questions under the biology category. You should get your answers more quickly that way :)
There are two things that happen before a parent cell divides:
1) DNA in the nucleus of the parent cell must replicate (this happens in the S phase of the cell cycle). If you're looking for a single answer to your question, then this is probably it.
2) Also, the cell must grow and some organelles (like the mitochondria) must also replicate before the parent cell divides. If organelles like the mitochondria did not replicate, then you would eventually end up with daughter cells that don't have enough mitochondria to support themselves.
Answer:
The answer to your question is: Cp = 0.129 J/g°C
Explanation:
Data
mass = 955 g of tungsten
T1 = 18°C
T2 = 100°C
Q = 10180 Joules
Cp = ?
Formula
Q = mCpΔT
Clear Cp from the equation
Cp = Q / mΔT
Substitution
Cp = 10180 / (955(100-18))
Cp = 10180 / (955(82))
Cp = 10180 / 78310
Cp = 0.129 J/g°C
Answer :
(A) The number of moles of ions per liter is, 0.1 moles/L
(B) The number of molecules of ion is,
(C) The pH of the solution will be, 4
<u>Solution for part A :</u>
First we have to calculate the pOH of the solution.
As we know that,
Now we have to calculate the moles of ion per liter.
<u>Solution for part B :</u>
First we have to calculate the ion concentration.
Now we have to calculate the number of molecules of ion
As, 1 mole contains number of molecules of ion
So, moles contains number of molecules of ion
<u>Solution for part C :</u>