Answer:
To check if it's properly cleaned.
Explanation:
When you finish using a microscope, you have to take out all your samples you were using and make sure it is completely clean so that no further contamination affects future sample analysis.
Also when you begin to use it, make sure it is clean so that when you analyze your sample(s) are free from other unexpected agents.
<span>In the question ' which of the following most likely require intermolecular force', options A and C given are definitely not the correct answers. Among the items listed in the questions, the one that will most likely required an intermolecular force is a rock maintaing its solid shape. Thus, the correct option is B. Intermolecular forces are forces which maintain chemical interactions between molecules of a particular susbstance and other types of paticles that may be present in the substance. Rocks are made up of differet particles and their structures are held together by different types of intermolecular forces depending on the types of particles present in the rock. Intermolecular forces can only occur among molecules and other particles in a compound that is why the other two options are wrong. Intermolecular force can either be attractive or repulsive. Attraction occurs between molecules of opposite charges, that is, positive and negative charges while repulsion occurs between particles of like charges, for intstance, between positive and positive charges. The Intermolecular forces that exist in a compound maintaings the integrity of the structure of that compound. Intermolecular forces in compounds exist in different forms, we have electrovalent bonds, covalent bonds, hydrogen bond, vander waals forces, etc. The type of molecules that exist in a compound will determine the type of intermolecular forces that will exist among the molecules of that substance. Electrovalent bonds are the strongest type of intermolecular force and it normally exist between metals and non metals. Covalent bonds involved sharing of electrons among the participating elements while vander waals forces are the weakest form of intermolecular forces. Forces are often required to break intermolecular forces apart. Breaking the intermolecular forces apart will destroy the structure of the substance inlvolved.</span>
Answer:
There's No Answer Im Sorry
Answer: 5.47m/s
Explanation:
Mass = 72.3kg
K.E = 1080.0J
V =?
K.E = 1 /2MV^2
V^2 = 2K.E /M = (2x1080)/72.3
V = sqrt [(2x1080)/72.3]
V = 5.47m/s
Answer:
The percent by mass of 3.55 g NaCl dissolved in 88 g water is 3.88%
Explanation:
When a solute dissolves in a solvent, the mass of the resulting solution is a sum of the mass of the solute and the solvent.
A percentage is a way of expressing a quantity as a fraction of 100. In this case, the percentage by mass of a solution is the number of grams of solute per 100 grams of solution and can be represented mathematically as:

In this way it allows to precisely establish the concentration of solutions and express them in terms of percentages.
In this case:
- mass of solute: 3.55 g
- mass of solution: 3.55 g + 88 g= 91.55 g
Replacing:

Percent by mass= 3.88%
<u><em>The percent by mass of 3.55 g NaCl dissolved in 88 g water is 3.88%</em></u>