The mass It is a physical property that indicates the amount of matter that a body or a particle possesses. Thanks to it, we can interact with our environment, and no matter how small or negligible the atoms or particles may seem, the cohesion between them multiplies their effects until they become tangible..
All objects have an associated mass; some are light or weightless, while others are massive or massive. Physically the mass holds many secrets, as well as numerous and intertwined definitions. On the other hand, chemically it is nothing more than a measure to be taken into account when carrying out industrial syntheses or in gravimetric analyzes..
Likewise, the mode and formulas used to calculate mass vary depending on the phenomenon considered (gravitational, electromagnetic, inertia, quantum, etc.); but in the end, its value will always be the same, since it is a constant at any point in the Universe (unless in the process a part is transformed into energy).
Electrons, protons, neutrons, atoms, molecules, planets, stars, and galaxies have a mass value made up of various types of matter. Where and how it originated are questions that physics constantly dedicates itself to investigating its answers.
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Chemically, mass is the amount of matter that a certain substance or compound possesses. It has no more relevance than concentration or molecular recognition in regard to catalytic reactions or in the development of mesoporous materials; but yes in the performance of these, the intermolecular interactions and their physical properties. In a laboratory the mass is measured with a scale or balance.
Although physically the concept is in principle the same, the mass pattern has remarkable characteristics in all its laws. For example, its definition according to Newton's second law, consists of the resistance that a body opposes to undergo an acceleration under the action of a force.
The more massive and "heavier" this object or body (a whale) is, the more difficult it will be to accelerate it in one direction in space. The opposite occurs with lightweight bodies (a portfolio).
In addition to this, mass is understood as a measure of how much a body interacts with a gravitational field, and how much the first can deform the second. This is where what is known by weight comes in, the difference in weight of the same object on various planets or regions of the Cosmos..
Mass is also the result, more currently, of the interactions or affinities that particles experience for the Higgs field that surrounds the entire Universe..
Mass is an extensive property, as it depends on the amount of matter, which is expressed in units of grams (g) or kilograms (kg). It's constant as long as it doesn't approach the speed of light, so it doesn't matter how large the field (gravitational, electronic, magnetic, etc.) you experiment with it is..
In addition to this, it is a scalar quantity and one of the seven fundamental quantities. Mass allows matter to exist as such and exhibit all its characteristics studied by physical or chemical analysis..
The smallest known mass as far as chemistry is concerned is that of the electron (9.110-31 kg). All atoms due to their very small mass are preferred to be expressed in terms of atomic mass units (amu), whose numerical values are equal to grams using the concept of Avogadro's number and moles.
The properties of the mass in chemistry do not escape the conventional; while in physics, the atomic nuclei of matter can decompose releasing abysmal amounts of energy, which leads to disobey the law of conservation of mass.
Depending on the system and the laws that govern them, the mass can be calculated from different formulas. For example, as far as Newtonian physics is concerned, mass is calculated by measuring the acceleration that a body acquires under a measurable force:
m = F / a
Knowing the weight and the acceleration generated by gravity:
m = W / g
Or the kinetic energy of the object:
m = 2Ec/vtwo
Another alternative is simply knowing the density of the object as well as its volume:
m = dV
In this way, the mass of a body is easily calculated by multiplying its density by its volume, in the case that it cannot be placed on a balance..
As far as chemistry is concerned, masses are always determined using a balance after or before experiments; even when these are not essentially gravimetric.
However, it is quite common to calculate how much of a reactant must be weighed on the balance to obtain a certain amount of moles or a concentration of the same once it is dissolved in a solvent. Have:
M = m / n
Where M is the molar mass, m the mass of the species, and n the number of moles. But it is also known that molarity is:
c = n / V
As the volume V of the solution to be prepared is known, as well as its concentration c, is calculated n and is substituted in the molar mass formula to obtain the mass of the reagent to be weighed.
There is a titanium sample with a volume of 23,000 cm3. Knowing that its density is 4.506 g / cm³, calculate the mass of said sample.
The formula for density is:
d = m / V
Solving for the mass we have:
m = dV
So it is only necessary to calculate by substituting the variables for the given values:
m = (4.506 g / cm³) (23.000 cm3)
= 103,638 g or 103.64 kg
You want to prepare 250 mL of a solution of potassium dichromate, KtwoCrtwoOR7, with a concentration of 0.63 M (mol / L). Calculate how much of KtwoCrtwoOR7 must be weighed on the balance. The molar mass of KtwoCrtwoOR7 is 294.185 g / mol.
From the formula
c = n / V
We remove the moles:
n = c V
= (0.63 M) (0.250 L)
= 0.1575 moles KtwoCrtwoOR7
Knowing the moles that must be in those 250 milliliters of solution, using the molar mass of KtwoCrtwoOR7 how much mass corresponds to this amount of matter is determined:
M = m / n
m = Mn
= (294.185 g / mol) (0.1575 mol KtwoCrtwoOR7)
= 46.3341 g
Therefore, 46.3341 grams of K are weighed on the balance.twoCrtwoOR7, they are dissolved and transferred in their respective solvent to a 250 mL balloon to finally fill up with water.
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