If an effusion experiment, it required 45 seconds for
a certain number of moles of an anknown gas to pass through
a small orifice into a vacuum. Under the same conditions, It required 18 seconds for the same number of moles of oxygen to effuse. Find the molecular mass of the unknown gas.​

Answer:

Sublimation is the transition of a substance directly from the solid to the gas state, without passing through the liquid state. ... The reverse process of sublimation is deposition or desublimation, in which a substance passes directly from a gas to a solid phase.

Answer:

6.02 X 1023 molecules

Explanation:

Answer:

False

Explanation:

It’s both living and non living

Answer:

False

Explanation:

In biospheres, there are both living and nonliving objects present! There are typically large abundances of living objects, such as animals, trees, grass, etc. There are also nonliving objects included in biospheres that are necessary for the prosperity of the living creatures! Examples of these nonliving objects include water for hydration, air for breathing, soil for growth, etc. A biosphere is where all living things are found on Earth, so the question is false since both types of things are found within them and not just nonliving things!

Answer:

A

Explanation:

more particles means things are heating up

Ex: Water. More bubbles form once water reaches it boiling point

Answer:

0.81mole

Explanation:

Given:

Volume of carbon monoxide  = 18dm³

Unknown

Number of moles of carbon monoxide  = ?

Solution:

To solve this problem;

           1 mole of any gas at rtp occupies a volume of 22.4dm³  

So;

           x mole of carbon monoxide will occupy a volume of 18dm³ at rtp

        22.4x  = 18

                x  = [tex]\frac{18}{22.4}[/tex]   = 0.81mole

Answer:

Contribute evidence; help us understand how people use resources.

Explanation:

Environmental science can be defined as an interdisciplinary field of science that comprises of chemistry, economics, engineering, zoology, geography, geology, biology, ecology, physics, etc., used for the study and understanding of various environmental factors, issues in relation to human life.

Many disciplines are involved in environmental science, including chemistry and biology which contribute evidence and economics and political science which help us understand how people use resources in the production of goods and services to meet the need or requirements of consumer. These resources include land, labor, entrepreneurship and capital.

Answer:

Solubility  = 2.142 x  [tex]10^{-4}[/tex] M

Explanation:

Solution:

Note: This question is incomplete and lacks necessary data to solve this question. But I have found similar question on the internet and fetched the necessary data to solve:

Missing Data:

Number of Moles of N2 dissolved per litre of blood = 5.357 x [tex]10^{-4}[/tex] M

As we know that, the air is approximately. 78 mol % of N2

N2 = 0.78

Partial pressure of the N2 at 100 ft:

Partial Pressure = 0.78 x (4.0)

Partial Pressure = 3.12 atm

Now, this is 4 times the pressure of nitrogen at 1 atm air pressure.

SO,

According to the Henry's Law, we have:

Solubility = k x [tex]P_{g}[/tex]

Here, k = 4 times

So,

Solubility = 4 x (5.357 x [tex]10^{-4}[/tex])

Solubility  = 2.142 x  [tex]10^{-4}[/tex] M

Answer:

C.

Explanation:

Phase change is physical.  

When Nitrogen gas forms a liquid is a physical change because it was only a state change from solid to liquid. Therefore, option C is correct.

A physical change takes place when some of the features of the matter change but the identity of the material does not. Physical changes can be categorized as reversible and irreversible. For example, the melting of water is reversible since the melted ice can be refrozen.

Physical change can be described as a kind of change where only physical properties of matter such as solubility, color, odor, etc. can change. During physical changes in matter, there will be no chemical bonds are broken or formed between atoms in the molecule.

The chemical composition as well as the chemical nature of the material will remain unchanged while a physical change.  The molecules can rearrange without changing the internal chemical composition of matter.

Therefore, changing the state of nitrogen gas is a physical change.

Learn more about physical change, here:

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Answer:

0.6 Ω

Explanation:

From the question given above, the following data were obtained:

Voltage (V) = 12 V

Current (I) = 20 A

Resistance (R) =?

From Ohm's law,

V = IR

Where:

V => is the voltage

I => is the current

R => R is the resistance

With the above formula, we can obtain the resistance as follow:

Voltage (V) = 12 V

Current (I) = 20 A

Resistance (R) =?

V = IR

12 = 20 × R

Divide both side by 20

R = 12 / 20

R = 0.6 Ω

Thus the resistance is 0.6 Ω

1.47 × 10²¹ molecules OF₂

Math

Pre-Algebra

Order of Operations: BPEMDAS

Chemistry

Atomic Structure

Stoichiometry

Step 1: Define

0.132 g OF₂

Step 2: Identify Conversions

Avogadro's Number

Molar Mass of O - 16.00 g/mol

Molar Mass of F - 19.00 g/mol

Molar Mass of OF₂ - 16.00 + 2(19.00) = 54.00 g/mol

Step 3: Convert

Step 4: Check

Follow sig fig rules and round. We are given 3 sig figs.

1.47204 × 10²¹ molecules OF₂ ≈ 1.47 × 10²¹ molecules OF₂

Answer:

Explanation:

35.453 u

Answer:

It makes chemicals hot or cold which makes chemicals react differently

Explanation:

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Answer:

Carbon dioxide is a product (cellular respiration)

Carbon dioxide is a reactant(photosynthesis)

Carried out in animals(cellular respiration)

Carried out in plants(both)

Chemical reaction(cellular respiration)

Oxygen is a product(photosynthesis)

Oxygen is a reactant(cellular respiration)

Produces usable energy source(photosynthesis)

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Answer:attached is the correct answer

Explanation:

Photosynthesis and Respiration

Answer:

Coefficients are used in all chemical equations to show the relative amounts of each substance present. This amount can represent either the relative number of molecules, or the relative number of moles (described below). If no coefficient is shown, a one (1) is assumed.

Explanation:

Answer with Explanation:

1. An "x-ray image" shows the difference between the bones and soft tissues because the bones appear white in color while the soft tissues appear gray in color.  

2. The reason behind the difference in the appearance of bones and soft tissues on the x-ray film is their density. Bones are denser than soft tissues, which means that its atoms are closely-knitted when compared to the soft tissues that are far apart from each other. This allows the x-ray radiation to be absorbed by the bone while it passes through most of the soft tissues.

This is the reason why pregnant women are advised not to undergo an x-ray examination because the fetus is denser and it will surely absorb the x-ray radiation.

An X ray is a X wave radiation that can penetrate from a high EMR and has wavelengths that are shorter than the UV rays. The concept of X rays where discovered in 1895.

Learn more about the x-ray image show differences between bone and soft.

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Answer:

40.34 g

Explanation:

First, we divide the heat to release by the heat of combustion to obtain the required moles of compound:

541.20 kJ/(1160.00 kJ/mol) = 0.4665 mol

So, we have to burn approximately 0.47 mol of the compound. We convert the moles to mass in grams by using the molar mass:

mass = molar mass x moles = 86.47 g/mol x 0.4665 mol = 40.34 g

Therefore, you must burn 40.34 grams of the compound to release 541.20 kJ of heat.

Answer:

F=500×3 = 1500 N

W = 1500×10 =15000 Nm

Answer:

Everything in Earth's system can be placed into one of four major subsystems: land, water, living things, or air. These four subsystems are called "spheres." Specifically, they are the "lithosphere" (land), "hydrosphere" (water), "biosphere" (living things), and "atmosphere" (air).

Explanation:

Answer:Waves.sry if this is wrong.

Explanation:

Answer:

It helps shape, while holding and keeping organelles in their place.

Explanation:

Answer:

it holds the cell organelles

Explanation:

You are welcome

Answer:

Magnesium

Explanation:

The element that could provide one atom to make an ionic bond with oxygen is magnesium.

Generally, most group II elements will form an ionic bond with oxygen with just one atom.

An ionic bond forms by the transfer of electrons from one specie to another.

Oxygen has a charge of 2-, to use one atom to form ionic bond with this specie, a magnesium atom with 2+ charge will bond with the specie.

 This will form:

                        MgO

This is notable for other group II elements.

Answer:

organs group together to form organ systems

Explanation:

Explanation:

Elements are pure substances made up of only atoms that all have the same number of protons in their nuclei. Compounds are molecules held together by covalent bonds. Ionic compounds are held together by ionic bonds. Intermetallic compounds are held together by metallic bonds. Certain complexes are held together by coordinate covalent bonds. A mixture is a combination of two or more elements or compounds which haven't bonded yet, so each mixture is it's own.

Hope this helps!

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