The energy in fossil fuels is often converted into

Answer:

A. to determine the efficiency of the reaction

Explanation:

Final answer:

The percent yield is calculated to assess the efficiency of a chemical reaction by comparing the actual yield to the theoretical yield. The correct option is (A).

Explanation:

Finding the percent yield of a reaction is necessary to determine the efficiency of the reaction, which is option A.

The percent yield is calculated by dividing the actual yield, the amount of product actually obtained from the reaction, by the theoretical yield, the maximum amount of product predicted by stoichiometry from the given amounts of reactants, and then multiplying by 100 to express it as a percentage.

The percent yield assesses how much product is obtained compared to what could have been obtained under ideal conditions. It reflects reaction efficiency, accounting for losses due to factors like incomplete reactions, side reactions, and difficulties in product recovery.

Answer:

Al₂(SO₄)₃ is the excess reactant.

Explanation:

Barium (Ba) react with Aluminium sulphate [Al₂(SO₄)₃] according to the following balanced equation:

It is clear that 3 mol of Ba react with 1 mol of Al₂(SO₄)₃ to give 3 moles of BaSO₄

The limiting reactant is the reactant that produces the least amount of BaSO ₄.

The molar masses of each substance involved.

Ba : 137.3 g/mol

Al₂(SO₄)₃: 342.1 g/mol

BaSO ₄:  233.3 g/mol

Then we calculate no of moles of each reactant from the given mass.

As following:

no. of moles of Ba = (mass /molar mass) = (1 g / 137.3 g/mol) = 0.0073 mol

no. of moles of Al₂(SO₄)₃ = (mass /molar mass)

                                         = (1.8 g / 342.1 g/mol) = 0.0053 mol

Then we calculate mol of product produced from each reactant

For BaSO₄

no of moles of BaSO₄ from Ba = (0.0073 * 3) / 3 = 0.0073 mol

then converting moles of BaSO₄ into mass

mass of BaSO₄ =  no of moles  * molar mass = 0.0073 * 233.3 = 1.7 g

For Al₂(SO₄)₃

no of moles of BaSO₄ from Al₂(SO₄)₃ = (0.0053 * 3) / 1 = 0.0159 mol

then converting moles of BaSO₄ into mass

mass of BaSO₄ =  no of moles  * molar mass = 0.0159 * 233.3 = 3.7 g

∴1 g of Ba  produces the least amount of barium sulfate, so it is the limiting reactant and Al₂(SO₄)₃ is the excess reactant.

Chemical formulas are used to describe the types of atoms and their numbers in an element or compound. The atoms of each element are represented by 1 or 2 different letters. When more that one atom of a specific element is found in a molecule, a subscript is used to indicate this in the chemical formula.

Subscripts in chemical formulas represent the number of atoms of each element in a molecule. They are used in molecular formulas to indicate the precise quantity of each atom present, and they differ from coefficients in chemical equations, which represent individual, unbonded atoms.

The purpose of subscripts in chemical formulas is to indicate the number of atoms of each type in the molecule. For instance, in the molecular formula H₂, the subscript '2' shows that there are two atoms of hydrogen in the molecule. It's crucial to differentiate this from coefficients in a chemical equation, where for example, 2H symbolizes two separate hydrogen atoms, not bonded as one unit.

A molecular formula, like H₂, uses chemical symbols and subscripts to represent the exact number of each kind of atom in the molecule, while an empirical formula expresses the simplest, whole-number ratio of atoms in a compound. A structural formula illustrates the bonding arrangement of the atoms. For instance, C₆H₆ shows that a molecule of benzene contains six carbon atoms and six hydrogen atoms.

It's worth noting that isotopes, which are atoms of the same element with different numbers of neutrons, do not affect the usage of subscripts in chemical formulas. The atomic mass of an element includes the weighted average of all its isotopes' masses.

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C) Summer

B) Full Moon

A) One (look up a lunar calendar, those can help with these question)

Hope this helps you :)

Answer:

I don't know much about that.. So i downloaded and posted above image..

Hope this helps you...

Final answer:

A primary standard solution has a known concentration due to its high purity and stability, used for precise analytical work. Secondary standards, such as NaOH solutions, must be standardized against a primary standard to determine their concentration and are typically easier to handle but require more frequent calibration.

Explanation:

The difference between primary and secondary standard solutions is based on their properties and uses in analytical chemistry. A primary standard is a reagent that has a known purity, a known stoichiometry, and is stable over time.

An example of a primary standard is a precisely weighed sample of K₂Cr₂O₇ which, when dissolved in a specific volume of solvent, provides a solution with a known molarity.

On the other hand, a secondary standard does not inherently have a known concentration and thus requires standardization with a primary standard before use. NaOH is a typical secondary standard, which needs to be titrated against a primary standard, such as potassium hydrogen phthalate, to determine its concentration accurately.

Using primary standards ensures high accuracy in quantitative analysis, whereas secondary standards are more practical and less costly but must be calibrated regularly to assure accurate results. This distinction is crucial when preparing solutions for tasks such as titrations or calibrating analytical equipment in a laboratory.

Answer:

m(94Be) = 9.012 182 24 amuN(protons) = 4N(neutrons) = 9 – 4 = 5m(protons) = (4 protons) (1.007 276 47 amu/proton) = 4.029 105 88 amum(neutrons) = (5 neutrons) (1.008 664 90 amu/neutron) = 5.043 324 50 amum(protons) + m(neutrons) = 4.029 105 88 amu + 5.043 324 50 amu = 9.072 430 38 amuMass defect m = 9.072 430 38 amu – 9.012 182 24 amu = 0.060 248 14 amum = (0.060 248 14 amu/nucleus) (1.6605 10-27kg/amu) = 1.0004 10-28 kg/nucleusE =mc2= (1.0004 10-28 kg/nucleus) (3.00 108m/s)2= 9.0038 10-12J/nucleusN(nucleons)= N(protons)+N(neutrons) = 9E =(9.0038 10-12J/nucleus) (1 nucleus/9nucleons) =1.0004 10-12J/nucleon2.

The mass defect is 0.059 948 14 amu and the Binding energy/nucleon of the nuclide is  9.66 × 10⁻¹² J/nucleon.

It is expressed as

[tex]\Delta M = (Zm_{P} + Nm_{n}) - M_{A}[/tex]

where

[tex]\Delta M[/tex] = Mass defect

[tex]M_{A}[/tex] = Mass of nucleus

[tex]m_{P}[/tex] = mass of proton

[tex]m_{n}[/tex] = mass of electron

Z = Number of proton

N = Number of neutrons

Now put the values in above formula we get

[tex]\Delta M = (Zm_{P} + Nm_{n}) - M_{A}[/tex]

[tex]\Delta M = 4(m_{p}) + 5 (m_{n}) - M_{A}[/tex]

       = 4 (1.007 276 47 amu) + 5 (1.008 664 90 amu) - 9.012 182 24 amu

       = 4.029 105 88 amu + 5.043 324 50 amu - 9.012 182 24 amu

       = 9.072 130 38 amu - 9.012 182 24 amu

       = 0.059 948 14 amu

It is expressed as

ΔE = Δmc²

where

ΔE = Binding energy

ΔM = change in mass

c = speed of light

Now put the values in above formula we get

ΔE = Δmc²

     = (0.59 984 14 amu) (1.6605 × 10⁻²⁷ kg/amu)  (3 × 10⁸) (m/s)²

Nucleons = 8.96 × 10⁻¹¹

Binding energy/nucleon = 9.66 × 10⁻¹² J/nucleon

Thus from the above conclusion we can say that The mass defect is 0.059 948 14 amu and the Binding energy/nucleon of the nuclide is  9.66 × 10⁻¹² J/nucleon.

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Answer:

0.268 L

Explanation:

concentration is the number of moles of solute in 1 L of solution

number of moles of KCl - 5.0 g / 74.5 g/mol = 0.067 mol

the concentration of the solution to be prepared - 0.25 mol/L

concentration = number of moles of KCl / volume of solution

substituting the values in the equation

0.25 mol/L = 0.067 mol / V

V = 0.268 L

solution should be diluted to 268 mL to make a 0.25 M solution

Final answer:

To prepare a 0.25 M KCl solution, 5.0 g of KCl should be diluted to approximately 268 mL.

Explanation:

To find out to what volume we should dilute 5.0 g of KCl to prepare a 0.25 M solution, we first need to calculate the number of moles of KCl. The molar mass of KCl is approximately 74.55 g/mol. Therefore, the moles of KCl in 5.0 g can be calculated by dividing the mass of KCl by its molar mass:

Moles of KCl = mass / molar mass = 5.0 g / 74.55 g/mol ≈ 0.067 moles

Since Molarity (M) is defined as moles of solute per liter of solution, we can rearrange the formula to solve for volume (V).

M = moles of solute / volume of solution in liters

V = moles of solute / M = 0.067 moles / 0.25 M ≈ 0.268 liters or 268 mL

Therefore, to prepare a 0.25 M solution of KCl, we need to dilute 5.0 g of KCl to approximately 268 mL.

Answer:

Explanation:

You simply have to multiply it by the molar mass =

m = 50mol SnSO4 x 214.773 g/mol

m = 10.738 g SnSO4

Answer:

Mass of 50 moles of tin(II) sulfate is 10,738 grams.

Explanation:

[tex]n=\frac{m}{M}[/tex]

Where:

n = moles of compound

m = mass of compound

M = molar mass of the compound

Moles of tin(II) sulfate , n= 50 moles

Molar mass of tin (II) sulfate , M= 214.77 g/mol

m = n × M

[tex]m=50 moles \times 214.77 g/mol=10,738 g[/tex]

Mass of 50 moles of tin(II) sulfate is 10,738 grams.

Answer:

-116.42°C

Explanation:

According to pressure law which states that the pressure of a fixed mass of a gas is directly proportional to its absolute temperature at constant volume.

Therefore;

P1/T1 = P2/T2

P1 = 811 mmHg

P2 = 415 mmHg

T1 = 33°C + 273°C = 306 K

Therefore;

T2 = P2T1/P1

    = (415 × 306)/ 811

    = 156.58 K

Therefore; temperature = 156.58 - 273 = -116.42°C

Answer:

-116.42°C

Explanation:

Answer:

It is the process in which a known amount of solution of known concentration is added to the concentration of the another solution to determine the concentration of unknown solution.

Explanation:

Answer:

Titration

Explanation:

Answer:

C stays the same

Explanation:

As a sample of a radioactive element decays, its half-life: remains the same.

A nuclear reaction can be defined as a type of reaction in which the nucleus of an atom of a radioactive element is transformed by being joined (fusion) or split (fission) with the nucleus of another atom.

In Chemistry, the half-life of a sample of a radioactive element would remain the same even as it experiences a decay of its sub-particles.

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Answer:

1.5 moles of H₂SO₄ needs 3.0 moles pf KOH to be neutralized.​

Explanation:

KOH → K⁺ + OH⁻.

H₂SO₄ → 2H⁺ + SO₄²⁻.

So, every 1.0 mole of KOH produces 1.0 mol of OH⁻.

While, every 1.0 mole of H₂SO₄ produces 1.0 mol of H⁺.

Thus, every mol of H₂SO₄ needs 2.0 moles of KOH to be neutralized.

So, 1.5 moles of H₂SO₄ needs (2 x 1.5 mol) = 3.0 moles pf KOH to be neutralized.​

C Kinetic Energy is the energy of motion

Final Answer:

The process occurring in the photograph of the glacier is Calving, where chunks of ice break off from the glacier's edge, forming icebergs in bodies of water.

B. Calving

Explanation:

Glacial calving is the process captured in the photograph of the glacier. Calving occurs when chunks of ice break off from the glacier's edge, forming icebergs in bodies of water. This process is primarily driven by the glacier's continuous movement and the mechanical stress caused by its own weight. Calving is a significant contributor to ice loss from glaciers and plays a crucial role in the dynamics of glacier systems.

In the photograph, the presence of large ice blocks breaking away from the glacier's terminus is a clear indication of calving. This process is influenced by a combination of factors, including the glacier's size, ice temperature, and the surrounding environment. As the glacier advances, the ice at its terminus experiences pressure and tension, eventually leading to the fracturing and separation of ice chunks. The resulting icebergs contribute to the redistribution of glacial ice and have implications for sea level rise.

Understanding the specific glacial processes at play, such as calving, is vital for assessing the impact of climate change on glacier dynamics and predicting potential consequences for sea level and environmental systems. Monitoring and studying such phenomena contribute to a more comprehensive understanding of Earth's changing landscapes.

Full Question:

2. Which process is occurring in this photograph of a glacier?

A. Melting

B. Calving

C. Abrasion

D. Plucking

Answer:

Sulfur belongs to the chalcogen family. Other members of the family are oxygen, selenium, tellurium, and polonium. These elements make up Group 16 (VIA) of the periodic table. The periodic table is a chart that shows how chemical elements are related to each other.

The term chalcogen comes from two Greek words meaning "ore forming." An ore is a naturally occurring mineral used as a source for an element. Many ores are compounds of a metal and oxygen or a metal and sulfur. Compounds that contain two elements, one of which is sulfur, are called sulfides. For example, a beautiful gold-colored mineral is called pyrite, or "fool's gold," because it looks so much like real gold. Pyrite is iron sulfide (FeS 2 ).

Sulfur was known to ancient peoples. Its physical and chemical properties are very distinctive. It often occurs as a brilliant yellow powder. When it burns, it produces a clear blue flame and a very strong odor.

SYMBOL

S

ATOMIC NUMBER

16

ATOMIC MASS

32.064

FAMILY

Group 16 (VIA)

Chalcogen

PRONUNCIATION

SUL-fur

Sulfur, also spelled as sulphur, is a very important element in today's world. Its most important use is in the manufacture of sulfuric acid (H 2 SO 4 ). There is more sulfuric acid made than any other chemical in the world. It has an enormous number of important uses.

Discovery and naming

Sulfur must have been well known to ancient peoples. They sometimes referred to it as brimstone. Sulfur sometimes occurs in bright yellow layers on the top of the earth. It has a sharp, offensive odor. When it burns, it gives off a strong, suffocating smell. The odor is like that produced when a match is struck.

The Bible mentions brimstone in a number of places. For example, Sodom and Gomorrah were two towns destroyed by God for the wicked ways of their citizens: "The Lord rained upon Sodom and upon Gomorrah brimstone and fire."

But ancient people certainly did not think about sulfur the way modern chemists do. In fact, they used the word "element" to talk about anything that was basic. Ancient Greek philosophers, for example, thought that everything consisted of four elements: earth, fire, water, and air. Other philosophers thought there were only two elements: sulfur and mercury.

But early thinkers were often confused as to what they meant by the word "sulfur." They often were talking about anything that burned and gave off large amounts of smoke. To them, "sulfur" was really a "burning substance." It took centuries for scientists to identify sulfur as an element.

Explanation:

The most chemically similar element like sulfur is oxygen.

Oxygen is the most similar element to sulfur.

Let's see the similarity between oxygen and sulfur:

Sulfur - 0.88

Oxygen - 0.48

Sulfur -  1.84

Oxygen - 1.40

Sulfur (2.5) is less electronegative than oxygen, (3.4)

Thus, oxygen is most similar to sulfur.

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Answer: Is there a list of birds, if not, it could be a seagull. They are arounf the water a lot and have sharp beaks which could possibily allow them to eat the same way as the eagle.

Birds that most likely catch and eat their food the way an eagle does include hawks and the African fish eagle. These birds, like the eagle, are raptors and utilize similar hunting and feeding techniques.

The question asks which bird most likely catches and eats its food in the same way as an eagle does. As the text mentions, eagles are examples of raptors, which are birds of prey. They use their clawed feet, also known as talons, to capture and kill their prey, which includes fish.

Similar to eagles, other birds that are known to catch and eat fish include the African fish eagle and hawk. All of these birds are adapted to hunting and consuming their prey similarly. Their sharp, hooked beak is perfect for tearing apart their prey and their strong legs and talons are well-equipped for grabbing and securing their catch.

Therefore, an African fish eagle or a hawk would most likely catch and eat its food the way an eagle does, flying with the fish to a safe location, such as a tree branch, before tearing it into small pieces to eat.

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Answer:

[tex]\boxed{\text{1000 g}}[/tex]

Explanation:

We know we will need a balanced equation with masses, moles, and molar masses, so let’s gather all the information in one place.

M_r:                           84.01  

              H₂SO4 + 2NaHCO₃ ⟶ Na₂SO₄ + 2CO₂ + 2H₂O

n/mol:         6

1. Use the molar ratio of NaHCO₃ to calculate the moles of NaHCO₃.

[tex]\text{Moles of NaHCO$_{3}$ = 6 mol H$_{2}$SO$_{4}$} \times \dfrac{\text{2 mol NaHCO$_{3}$}}{\text{1 mol H$_{2}$SO$_{4}$}}\\=\text{12 mol NaHCO$_{3}$}[/tex]

2. Use the molar mass of NaHCO₃ to calculate the mass of NaHCO₃.

[tex]\text{Mass of NaHCO$_{3}$ = 12 mol NaHCO$_{3}$} \times \dfrac{\text{84.01 g NaHCO$_{3}$}}{\text{1 mol NaHCO$_{3}$}}\\\\= \text{1000 g NaHCO$_{3}$}[/tex]

You must use [tex]\boxed{\textbf{1000 g}}[/tex] of NaHCO₃.

repel each other because they have like charges

Answer:

the type of nuclear reaction cased is fission

Explanation:

Answer:

C. Ca.

Explanation:

The atom loses or gains electrons forming anion or cation to reach stability (fill the outermost shell of the electron levels).

When atom gains electrons forms anions with negative charge.

While, when atom loses electrons forms cations with positive charge.

A. O:

O atom has 8 electrons in its nucleus and gains 2 electrons to reach stability (10 electrons, configuration of Ne).

So, it forms O²⁻.

B. AI:

Al atom has 13 electrons in its nucleus and loses 3 electrons to reach stability (10 electrons, configuration of Ne).

So, it forms Al³⁺.

C. Ca:

Ca atom has 12 electrons in its nucleus and loses 2 electrons to reach stability (10 electrons, configuration of Ne).

So, it forms Ca²⁺.

D. Na:

Na atom has 11 electrons in its nucleus and loses 1 electron to reach stability (10 electrons, configuration of Ne).

So, it forms Na⁺.

Answer:

Carbon forms the key component for all known life on Earth.

Explanation:

Complex molecules are made up of carbon bonded with other elements, especially oxygen and hydrogen and frequently also with nitrogen, phosphorus and sulfur. Carbon is abundant on Earth. It is also lightweight and relatively small in size, making it easier for enzymes to manipulate carbon molecules.

Answer:

Pure Beryl is colorless.

Explanation:

The wide range of impurities cause the diverse amount of colors and many varieties. The green color in emerald is usually caused by traces of the element chromium, and the blue color of aquamarine usually by iron.

The element that beryl, emeralds, and aquamarine have in common is beryllium.

Beryl is a mineral composed of beryllium aluminum cyclosilicate (Be3Al2Si6O18). When beryl is pure and green in color due to traces of chromium and sometimes vanadium, it is known as emerald, which is a precious gemstone. On the other hand, when beryl is blue to blue-green in color due to traces of iron, it is known as aquamarine, another valuable gemstone.

Answer:

Explanation:The silica tetrahedron is a molecule containing four oxygen atoms and one silicon atom. It resembles a triangular pyramid, with the silicon atom located in the middle and one oxygen atom located at each of the four corners.

The structure of olivine is described as isolated tetrahedral because each tetrahedron is bonded to either a magnesium ion or an iron ion.

Although some minerals always appear the same color, many vary in color due to trace elements within the mineral. These trace elements can alter the mineral’s coloring.

Minerals with a metallic luster do not allow light to pass through. Minerals with a nonmetallic luster do allow light to pass through.

In minerals, cleavage refers to breaks that occur along a specific plane. Fractures refer to irregular breaks.

Answer:

1.The silica tetrahedron is a molecule containing four oxygen atoms and one silicon atom. It resembles a triangular pyramid, with the silicon atom located in the middle and one oxygen atom located at each of the four corners.

2.The structure of olivine is described as isolated tetrahedral because each tetrahedron is bonded to either a magnesium ion or an iron ion.

3.Although some minerals always appear the same color, many vary in color due to trace elements within the mineral. These trace elements can alter the mineral’s coloring.

4.Minerals with a metallic luster do not allow light to pass through. Minerals with a nonmetallic luster do allow light to pass through.

5.In minerals, cleavage refers to breaks that occur along a specific plane. Fractures refer to irregular breaks.

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Final answer:

A manufacturing plant polluting a river is an example of point source pollution because the pollution originates from a single, identifiable location. Correct option is A. point source

Explanation:

A manufacturing plant that has been found guilty of polluting the nearby river is an example of point source pollution. Point source pollution is characterized by contaminants entering a water body at a specific, identifiable location, such as a discharge pipe from a factory. This type of pollution, unlike nonpoint source pollution, comes from a single, identifiable source and is typically easier to manage and control because it originates from a fixed location.

On the other hand, nonpoint source pollution occurs when pollutants are introduced into water bodies from widespread areas, making the exact point of origin difficult to identify. Fertilizers applied to residential lawns and gardens, for instance, can end up in water bodies through nonpoint-source processes like surface run-off or movement through groundwater.

Answer:

Elements in group 15 will gain electrons and it will gain 3 electrons to obtain a noble gas structure.

Explanation:

A noble gas structure is obtained when it completes a full octet around the atom. Meaning it has 8 electrons in its outer shell.

Group 15 is also known as Group 5A or the Nitrogen group. The nitrogen group have 5 valence electrons. Now something to remember about gaining and losing electrons. When the outershell is more than half full, it is more likely to attract electrons to itself. When the outershell is less than half full, it is more likely to lose electrons.

So in the case of group 15, which has 5, it is closer to 8, so it will gain an electron. To complete the octet, it will need 3 more electrons.

Answer:

C. Maria

Explanation:

The ocean floor is made of basaltic rocks that have upwelled from the mantle.

The surface of the moon is typified by this rock type too. Several Volcanoes on the surface of the moon are basaltic in composition.

Answer:

= 2.659 g NaCl

Explanation:

Molarity of a substance is given by the formula;

Molarity = moles/Volume in liters

Thus;

Number of moles = Molarity ×  volume in liters

                              = 1.3 M × 0.035 L

                              = 0.0455 Moles

But, the molar mass of NaCl is 58.44 g/mol

The mass of NaCl is therefore;

     = 0.0455 g × 58.44 g/mol

     = 2.659 g NaCl

The mass of NaCl in a 35-mL sample of a 1.3 M NaCl solution is approximately 2.7 g.

To calculate the mass of NaCl in a 35-mL sample of a 1.3 M NaCl solution, you need to start with the definition of molarity, which is moles of solute per liter of solution. First, convert the volume of the solution from milliliters to liters by dividing by 1000. Therefore, 35 ml equals 0.035 L.

Knowing that molarity(M) = mole/liters, we can use the given molarity to find out that there are 0.0455 moles of NaCl in our solution since (1.3 mol/L) × (0.035 L) = 0.0455 Mol.

Finally, use the molar mass of NaCl (58.44 g/mol) to convert this molar quantity into grams. That is (0.0455 Mol) × (58.44g/mol) = 2.66 g. So, the mass of NaCl in the solution is approximately 2.7 g.

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Answer:

Chemical reaction

Explanation:

Answer:

The environment changes causing the animals to adapt.

Answer:

Human ears can hear sound waves that vibrate in the range from about 20 times a second (a deep rumbling noise) to about 20,000 times a second (a high-pitched whistling). (Children can generally hear higher-pitched sounds than their parents, because our ability to hear high frequencies gets worse as we get older.) Speaking more scientifically, we could say that the sounds we can perceive have a frequency ranging from 20–20,000 hertz (Hz). A hertz is a measurement of how often something vibrates and 1 Hz is equal to one vibration each second. The human voice makes sounds ranging from a few hundred hertz to a few thousand hertz.

Suppose you could somehow hit a drum-skin so often that it vibrated more than 20,000 times per second. You might be able to see the skin vibrating (just), but you certainly couldn't hear it. No matter how hard you hit the drum, you wouldn't hear a sound. The drum would still be transmitting sound waves, but your ears wouldn't be able to recognize them. Bats, dogs, dolphins, and moths might well hear them, however. Sounds this like, with frequencies beyond the range of human hearing, are examples of ultrasound.

Ultrasound is sound or other vibrations having an ultrasonic frequency, particularly as used in medical imaging. Also, Infrasound is sound waves with frequencies below the lower limit of human audibility