what is actually chemistry​

Answer:

Historically, wood was the main source of U.S. energy until the mid-1800s and was the only commercial-scale renewable source of energy in the United States until the first hydropower plants began producing electricity in the 1880s.

The Advantages of Renewable Energy Resources-A Fuel Supply That Never Runs Out.Zero Carbon Emissions.Cleaner Air and Water.Disadvantages of Renewable Energy-he Electricity Generation Capacity is Still Not Large Enough.Renewable Energy Can be Unreliable.

First, we need to take advantage of the world's abundant natural gas resources and reduce coal consumption;

Second, governments must support development of carbon capture and storage technology to make fossil fuel use cleaner;

Explanation:

We can convert strontium-82 to rubidium-82 by positron emission.

The three main fundamental subatomic particles in an atom are;

In a neutral atom, the number of protons is always equal to the number of electrons.

In strontium-82, there are 44 neutrons, 38 electrons and 38 protons. In rubidium-82, there are 45 neutrons, 37 electrons and 37 protons. We can convert  strontium-82 to rubidium-82 by positron emission.

Learn more about positron emission: https://brainly.com/question/11594309

Answer:

a

Explanation:

Answer:

U shaped vallies?

Explanation:

(i dont know if this was one of the options)

Answer:

21% oxygen and 78%nitrogen

Explanation:

Answer:

Nitrogen and Oxygen

Explanation:

nitrogen - 78 %

oxygen - 21%

To find the force,

 ⇒ must know the force's formula ⇒ F = MA

Let's consider the information given:

Let's solve:

  [tex]F=MA=0.025kg*5m/s^2=0.125N[/tex]

Thus the force is 0.125N

Answer: 0.125N

Hope that helps!

Answer:

2) To find the atoms from the moles, you just multiply Avogadro's number (6.02 x 10^23) by the moles.

So 3.35 x (6.02 x 10^23) = 2.0167 x 10^24 atoms are in 3.35 moles of aluminum

3) If the question is asking under standard temperature and pressure, we know that if we divide the volume by the molar volume of a gas (which is 22.7 in standard temperature and pressure), we can get the moles.  

So 101.25L / 22.7 = 4.46 mol

4) We know that to find the moles, it is the mass divided by the molar mass. If we rearrange the equation to solve for mass, we have to multiply the moles by the molar mass to get there.

Nitrogen's (N) molar mass on the periodic table is 14g/mol, but since Nitrogen is a diatomic element, it would be N2 by itself. So multiply 14 by 2, which will give you 28g/mol. N2's molar mass is 28g/mol.

Now you multiply 13.7 moles by 28g/mol, which will give you 383.6g

Just did a few edits here, 4.46 for question 3 is in moles not L

Taking into account the definition of avogadro's number,

2. 3.35 moles of aluminum contains 2.018ײ⁴ atoms.

3. 4.52 moles of CO₂ gas are in a 101.25 L container filled with CO₂ gas.

4. 13.7 moles of N₂ contain 383.6 grams.  

Avogadro's Number is called the number of particles that make up a substance (usually atoms or molecules) and that can be found in the amount of one mole of said substance. Its value is 6.023×10²³ particles per mole. Avogadro's number applies to any substance.

Then you can apply the following rule of three: if 1 mole of aluminum contains 6.023×10²³ atoms, then 3.35 moles of aluminum contains how many atoms?

amount of atoms of aluminum= (6.023×10²³ atoms × 3.35 moles)÷ 1 mole

amount of atoms of aluminum=2.018ײ⁴ atoms

Finally, 3.35 moles of aluminum contains 2.018ײ⁴ atoms.

The STP conditions refer to the standard temperature and pressure. Pressure values at 1 atmosphere and temperature at 0 ° C are used and are reference values for gases. And in these conditions 1 mole of any gas occupies an approximate volume of 22.4 liters.

Then, you can apply the following rule of three: If by definition of the STP conditions 1 mole of CO₂ occupies a volume of 22.4 L, how many moles does 101.25 L occupy?

[tex]amount of moles of CO_{2} =\frac{101.25 Lx1 mole of CO_{2} }{22.4 L}[/tex]

amount of moles of CO₂= 4.52 moles

4.52 moles of CO₂ gas are in a 101.25 L container filled with CO₂ gas.

The molar mass of substance is a property defined as its mass per unit quantity of substance, in other words, molar mass is the amount of mass that a substance contains in one mole.

In this case, the molar mass of N₂ is 28 g/mole. So, you can apply the following rule of three:  If 1 mole of N₂ contains 28 grams, 13.7 moles of N₂ contain how much mass?

[tex]mass=\frac{13.7 moles x28 grams}{1 mole}[/tex]

mass= 383.6 grams

13.7 moles of N₂ contain 383.6 grams.

Learn more about

Answer:

Mn(NO3)3 Molar mass = (54.93) + (3 x 14) + (9 x 16) = 240.93g/mol

Total number of Oxygen atoms in formula = 9

Total mass of oxygen atoms theoretically in the formula = 9x16 = 144g/mol

Oxygen's percentage composition:

(144/240.93) x 100 = 59.7% of the compound is oxygen

Using thermodynamics

[tex]\\ \sf\longmapsto Q=mc∆T[/tex]

[tex]\\ \sf\longmapsto Q=0.015(328)(4184)[/tex]

[tex]\\ \sf\longmapsto Q=20585.28J[/tex]

The law of conservation of mass states that

In any chemical reaction mass is neither created nor destroyed rather it remains conserved

Look the chemical reaction below

[tex]\\ \sf\longmapsto 2H_2+O_2=2H_2O[/tex]

Count the mass on both sides and simplify

Explanation:

Because of the earth and climate change the point of incidence mean that you mean by engineers to social evils activities.

Answer:8.334×10^-6 moles

Explanation:

a mole is 6.023×10^23

5.02×10^18 ÷ 6.023×10^23=8.33×10^-6

Answer: A change in color is not always a chemical change. If one were to change the color of a substance in a non-chemical reaction scenario, such as painting a car, the change is physical and not chemical.

Solid → Liquid: Melting

Solid → Gas: Sublimation

Liquid → Gas: Vaporization

Gas → Liquid: Condensation

Explanation:

Answer:

increase

Explanation:

Let's suppose we have a sample of air in a closed container. We heat the container and we want to predict what would happen to the pressure.

According to Gay-Lussac's law, the pressure of a gas is directly proportional to its absolute temperature.

Thus, if we increased the temperature of the air by heating it, its pressure would increase.

If a sample of air in a closed container was heated, the total pressure of the air would increase.

Answer:

Explanation:

The ionization energy is required to cause a gaseous atom or ion to release a electron.

Answer:

Explanation:

This is just a ratio question. Factor of increase = 27.2 / 3.20 = 8.50

To solve such this we must know the concept of double displacement reaction. Therefore, the correct option is option B that is kinetic energy of collisions of reactant particles.

Chemical reaction is a process in which two or more than two molecules collide in right orientation and energy to form a new chemical compound. The mass of the overall reaction should be conserved. There are so many types of chemical reaction reaction like combination reaction, double displacement reaction.

There are so many factors that affects the rate of reaction, among these, kinetic energy of collisions of reactant particles affect the rate of a chemical reaction. the rate of reaction is directly proportional to the rate of chemical reaction.

Therefore, the correct option is option B.

Learn more about the chemical reactions, here:

https://brainly.com/question/3461108

#SPJ2

Answer: In the core of the Sun hydrogen is being converted into helium. This is called nuclear fusion. It takes four hydrogen atoms to fuse into each helium atom. During the process some of the mass is converted into energy.

Answer:

Explanation:

Taking into account the definition of Avogadro's Number, the correct answers are:

1 mole of any element contains 6.023×10²³ atoms

1 mole of any compound contains 6.023×10²³ molecules

You have to know that Avogadro's Number or Avogadro's Constant is called the number of particles that make up a substance (usually atoms or molecules) and that can be found in the amount of one mole of said substance. Its value is 6.023×10²³ particles per mole.

Avogadro's number represents a quantity without an associated physical dimension, so it is considered a pure number that allows describing a physical characteristic without an explicit dimension or unit of expression.

Avogadro's number applies to any substance, because the number of elementary units in a mole of a substance is, by definition, a  constant that does not depend on the material or the type of particle considered.

So, in this case, the correct answers are:

1 mole of any element contains 6.023×10²³ atoms

1 mole of any compound contains 6.023×10²³ molecules

hope that help you mark me as brinilylist pls

Answer:

D

Explanation:

Given that the molar mass of NaCl is 58.44 g/mol, we want to determine the molarity of a solution that contains 87.75 g of NaCl in 500. mL of solution.

Recall that molarity is given by:

[tex]\displaystyle \text{M} = \frac{\text{ mols solute}}{\text{ liters soln.}}[/tex]

Therefore, we can convert the amount of NaCl in the solution to moles of NaCl and the volume from milliliters to liters:

[tex]\displaystyle \begin{aligned} \text{M} & = \frac{(87.75 \text{ g NaCl})}{(500. \text{ mL soln.})} \cdot \frac{1 \text{ mol NaCl}}{58.44 \text{ g NaCl}} \cdot \frac{1000 \text{ mL soln.}}{1 \text{ L soln.}} \\ \\ & = 3.00\text{ } \frac{\text{mol NaCl}}{\text{ L soln.}} \\ \\ & = 3.00 \text{ M} \end{aligned}[/tex]

Hence, our answer is D.

A wave with a smaller wavelength has UV radiation energy than one with a larger wavelength.

Uses of UV Rays

▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬

Answer: anemia because Marie curie died of anemia

Answer: possibly diffusion

Explanation:

all particles are in motion unless at a certain degree so they'd spread throughout the room diluting as they continue to spread out.

Answer:

In the Lewis structure for IF5 you'll need to put a total of 12 valence electrons on the Iodine atom in order to draw the Lewis structure. Remember that Iodine (I) can hold more than eight valence electrons. For the IF5 Lewis structure, calculate the total number of valence electrons for the IF5 molecule

Explanation:

I be knowing hope this helps