A physical change<span> in a substance doesn't </span>change<span> what the substance is. In a </span>chemical change<span> where there is a </span>chemical reaction<span>, a new substance is formed and energy is either given off or absorbed.</span>
PE, GO, XY - I am probably wrong xoxoxoxoxxo
The claim is that NaCl mixture is a homogeneous mixture.
Homogeneous mixture means that the components of the mixtures cannot be determined or separated by the naked eye. However, these components can be separated using physical means, such as boiling, evaporation and condensation which will be used in this experiment.
First, we need to prepare one molar solution of NaCl. To do so, we will dilute a mass of 58.44 grams (molar mass of NaCl) in 1 liter of water.
By this, we will have NaCl solution.
We can notice that once the NaCl is diluted in water, all what you can see is a clear solution. You cannot see the separate particles of NaCl in water.
..............> observation I
Now, we will heat this solution until it boils and water starts evaporating. We will place a cold surface above the steam coming out from the boiling solution.
What we will observe is that when all the water evaporates, we can see white precipitate of NaCl in the bottom of the container. Examining the cold surface placed above the steam, we can see that the water has condensed on this surface.
.........>observation II
Based on this, we managed to use boiling, evaporation and condensation (physical methods) to restore the components of the solution separately.
.............>conclusion
Based on observation I, observation II and the conclusion. we were able to prove that NaCl solution is a homogeneous mixture.
Answer:
the volume delivered by the pipette = 22.32 mL
Explanation:
To calculate this, let us first note that the density of water relates it weight and its volume (density = mass ÷ volume), hence we are going to use density to determine the volume.
Density of water = mass/volume = 0.997 g/ mL
mass = 22.25g
Density = 0.997g/mL
volume = ?
∴ the volume delivered by the pipette = 22.32 mL
<em>Please note that this calculation is based on the fact that the weight of the empty flask has been determined and canceled out.</em>
