in the nuclues
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Answer:
2
Explanation:
Pure water is not a mixture....it is only water
gold ...is only gold
2. air IS a mixture of various gases.....nitrogen , oxygen, co2 etc
Option 2: The air in your room. The air in your room is an example of a mixture because it consists of various gases that can be separated from each other.
The correct answer is Option 2: The air in your room.
A mixture is a combination of two or more substances that are not chemically bonded together. The air in your room is a mixture because it consists of various gases such as oxygen, nitrogen, carbon dioxide, and others. Each gas retains its individual properties and can be separated from the others.
On the other hand, pure water is a compound because it consists of two hydrogen atoms bonded to an oxygen atom, while gold is an element because it is composed of only gold atoms.
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(2) milliliters
(3) joules per kilogram
(4) moles per liter
The concentration of a solution can be expressed in (4) moles per liter
Stoichiometry in Chemistry learn about chemicals mainly emphasizes quantitative, such as the calculation of volume, mass, number, which is related to numbers, molecules, elements, etc.
In the reaction there are also manifestations of reagent substances namely gas (g), liquid (liquid / l), solid (solid / s) and solution (aqueous / aq).
The concentration of a substance can be expressed in several quantities such as moles, percent (%) weight / volume,), molarity, molality, parts per million (ppm) or mole fraction. The concentration shows the amount of solute in a unit of the amount of solvent.
Temperature is used as a guide to the level of heat energy from objects
Temperature cannot be measured by the surface of the hand because it is not accurate but can be measured by a thermometer. Temperature units include Celsius, Fahrenheit, Reamur or Kelvin
Volume is a derivative quantity derived from the length
The unit of volume can be expressed in liters or milliliters or cubic meters
Energy can be interpreted as the ability to do work
Energy units can be stated in joules or calories (J or Cal)
Mole
The mole itself is the number of particles contained in a substance amounting to 6.02.10²³
Mole is the result of dividing the amount of substance mass and its molar mass
Molarity is a way to express the concentration of the solution
Molarity shows the number of moles of solute in every 1 liter of solute or mmol in each ml of solution
Where
M = Molarity
n = Number of moles of solute
V = Volume of solution
So to find the number of moles can be expressed as
the concentrations for the two ions
The molarity of the stock solution of luminol
volume of 0.100 M Na₃PO₄
Answer:
2.53 grams of hydrogen gas will be produced and 12.2 many grams of the excess reactant i.e. calcium will be left over.
Explanation:
Moles of calcium =
Moles of HCl =
According to reaction, 2 moles of HCl reacts with 1 mole of calcium :
Then 2.53 moles of HCl will recat with :
of calcium.
As we can see moles of calcium are in excessive amount. Hence calcium is an excessive reagent.
Moles of calcium left unreacted =1.57 mol - 1.265 mol =0.305 mol
Mass calcium left unreacted = 0.305 mol × 40 g/mol =12.2 g
Since, calcium is an excessive reagent HCl is limiting reagent and the amount of hydrogen gas produced will depend on HCl .
According to reaction, 2 moles of HCl gives 1 mole of hydrogen gas.
Then 2.53 moles of HCl will give:
of hydrogen gas.
Mass of 1.265 mol of hydrogen gas = 1.265 mol × 2 g/mol = 2.53 g
2.53 grams of hydrogen gas will be produced and 12.2 many grams of the excess reactant i.e. calcium will be left over.
Answer:
2.55 g of hydrogen
12.17 g calcium.
to nearest hundredth.
Explanation:
The balanced equation is:
Ca + 2HCl ---> CaCl2 + H2
Using the atomic masses
40.078 g Ca react with 72.916 g of HCl to give 2.016 g HCl
The ratio of Ca to HCl in the above is 1 to 1.81935
so 62.8 g Ca reacts with 62.8 * 1.81935 = 114.245 g HCl
so there is excess of Ca in the given weights.
Therefore the mass of Hydrogen produced
= (2.016 / 72.916) * 92.3
= 2.552 g of hydrogen gas.
The mass of calcium required to produce 2.552 g of hydrogen is:
(2.552 / 2.016) * 40.078
= 50.73 g
So the excess of calcium is 62.8 - 50.73
= 12.17 g.
The pH of a solution depicts the alkalinity or the acidity of the components of the solution and is given as a negative log function of hydrogen ions.
The pH of the solution is:
2
The pH can be estimated as:
Therefore, 2 is the pH of the solution.
To learn more about pH follow the link:
less
equally as
twice as
Answer:
Ice is Less Dense than water
Explanation:
If you put ice in water the ice won't sink to the bottom because water is denser then ice.
:)
The lattice energy in the formation of one mole of BaSe bonds can be calculated using the equation Ulattice = (k * e2) / r, where k is the proportionality constant, e is the charge of the ions, and r is the distance between the ions. Given the radius of the barium ion and selenide ion, we can calculate the distance between them and then use it in the equation to find the lattice energy. The lattice energy in this case is approximately 10.8 billion N.
The amount of energy released in the formation of one mole of BaSe bonds can be calculated using the concept of lattice energy. Lattice energy is the energy released when ions come together to form a solid lattice structure. In this case, we have a barium ion (Ba2+) and a selenide ion (Se2-) coming together to form BaSe bonds.
To calculate the lattice energy, we can use the equation:
Ulattice = (k * e2) / r
Where:
Given that the radius of the barium ion is 1.35 Å and the radius of the selenide ion is 1.98 Å, we can calculate the distance between them and then use that value in the equation to find the lattice energy.
Let's calculate it:
Distance between ions = radius of Ba ion + radius of Se ion
= 1.35 Å + 1.98 Å
= 3.33 Å
Converting to meters:
= 3.33 * 10-10 m
Now, substituting the values in the equation:
Ulattice = (8.99 * 109 Nm2/C2) * (2 * 2) / (3.33 * 10-10 m)
= 10791849712.91 N
Therefore, the amount of energy released in the formation of one mole of BaSe bonds (lattice energy) is approximately 10.8 billion N.
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