A gas in a 6.2 mL cylinder has a pressure of 1.4 atmospheres. A piston is pushed in

until the gas volume is 3.1 mL, while the temperature remains constant. What's the

final pressure of the gas in the cylinder?

A) 2.8 atm

B) 4.8 atm

C) 3.2 atm

OD) 5.6 atm

Answers

Answer 1

Answer:

A) 2.8 atm

Explanation:


Related Questions

An experiment looking at structures smaller than a cell would most likely employ a
1) dissecting microscope
B) transmission electron microscope
3) scanning electron microscope
D) compound light microscope

Answers

Answer:

The correct answer is - b. transmission electron microscope.

Explanation:

A transmission electron magnifying instrument fires a light emission through an sample to create an amplified and magnified picture of a specimen.

The transmission electron magnifying instrument is utilized to see thin slices of specimen or specimen smaller than 100 nm through which electrons can pass and form a image of specimen. The TEM is comparable to from various perspectives to the ordinary light magnifying instrument.

Thus, the correct answer is - b. transmission electron microscope.

How many moles of CO2 are produced
if 6 moles of O2 are used?
C6H12O6 + 602 + 6CO2 + 6H2O

Answers

Answer:

6 moles

Explanation:

Forst of all arrange the equation, it isn't in the right order and I suppose the equation is of aerobic respiration:

That is :

C6H12O6 + 6O2 ---------> 6CO2 + 6H20 + 2830kJ (energy)

Then use the ratio which can be seen by the balancing:

02 : CO2

6: 6

The ratio clearly shows how much moles of CO2 are produced; 6 moles

The term mole concept is used here to determine the moles of carbon dioxide produced. The moles of CO₂ produced from the given reaction is 6.

What is a mole?

One mole of a substance is defined as that quantity of it which contains as many entities as there are atoms exactly in 12 g of carbon - 12. The formula used to calculate the number of moles is:

Number of moles = Given mass / Molar mass

The balanced equation for the oxidation reaction of glucose is given as:

C₆H₁₂O₆ + 6O₂ → 6CO₂ + 6H₂O + E

In a balanced equation the number of atoms of reactants and products on both sides of the equation are equal. The number of 'C', 'H' and 'O' atoms on both sides of the equation are equal.

Here the number of moles of CO₂ produced from 6 moles of oxygen is 6.

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100 POINTS & BRAINLIEST !!!! PLEASE HELP

Answers

Answer:

independent: type of liquid

dependent: growth of plant

control: time

constant: time

constant: time

hypothesis: If I water the plant with water, it will grow the most because water is the liquid that sustains life on earth.

Explanation:

A silicon atom has an atomic number of 14. What information does the atomic number tell you? (Choose all possible answers)
Group of answer choices

Silicon atoms have 14 protons.

Silicon atoms will react with other atoms in order to gain stability.

Silicon atoms are stable in their elemental form

Silicon atoms have 14 electrons.

Answers

Answer:

Silicon atoms have 14 protons.

Silicon atoms will react with other atoms in order to gain stability.

Silicon atoms have 14 electrons.

Explain why each molecule has a higher boiling point than the other in the pair Match the words in the left column to the appropriate blanks in the sentences on the right. Make certain each sentence is complete before submitting your answer. exhibits dispersion forces The main reason that NO, has a higher boiling point than CO, is that NO
exhibits hydrogen bonding
has a larger molar mass
exhibits dipole-dipole The main reason that NHa has a higher boiling point than CHs is that NH
The main reason that CS2 has a higher boiling point than CO2 is that CS forces exhibits ion-dipole forces

Answers

Answer:

The main reason that NO, has a higher boiling point than CO is that NO has a larger molar mass.

The main reason that NH3 has a higher boiling point than CH4 is that NH exhibits hydrogen bonding.

The main reason that CS2 has a higher boiling point than CO2 is that CS2 has a larger molar mass.

Explanation:

The larger the molecular mass, the greater the surface area of the molecule and the greater the magnitude of dispersion forces. Hence, among nonpolar molecules, increase in molecular mass leads to a higher boiling point due to stronger dispersion forces.

Though CO and NO possess dipole-dipole forces, NO has a greater molar mass than CO, hence it has a higher boiling point than CO.

NH3 exhibits intermolecular hydrogen bonding hence it has a much higher higher boiling point than CH4 irrespective of the fact that their molar masses are close in magnitude.

Answer:

The main reason that NO2 has a higher boiling point than CO2 is that NO2 exhibits dipole-dipole forces.

The main reason that CS2 has a higher boiling point than CO2 is that CS2 has a larger molar mass.

The main reason that NH3 has a higher boiling point than CH4 is that NH3 exhibits hydrogen bonding.

What does ultraviolet light from the sun do with oxygen gas.

Answers

Answer:

Gases in Earth's atmosphere form a protective layer

Nitrogen, oxygen and ozone molecules in the upper atmosphere and stratosphere absorb ultraviolet light from the Sun, providing a shield that prevents this radiation from passing to the Earth's surface.

Explanation:

i got this from  

...www.aeronomie.be

An electrically neutral atom bears what trait?
A) It contains protons in its nucleus.
B) It contains the same number of protons and neutrons.
C) It contains the same number of electrons and protons.
D) It contains electrons in its electron shells.

Answers

C) It contains the same number of electrons and protons.

ILL GIVE BRAINLIEST ⏳⏳⏳⏳⏳⌛◑﹏◐ Lorenzo is making a prediction. “I learned that nonmetals increase in reactivity when moving from left to right. So I predict that xenon will be more reactive than iodine.” Is Lorenzo correct? If so, why? If not, explain his error.

Answers

No, he is not correct. Xenon is not very reactive since it is located in the group of noble gases. The noble gases are all chemically unreactive gases.Elements within different groups within the periodic table have different physical and chemical properties. Hope this answers the question.

Answer:

Answer is no because,

Explanation:

Iodine is LESS REACTIVE than the elements above it in group 17 (fluorine, chlorine and bromine) it still forms compounds with many other elements. Although iodine is a non-metal, it displays some METALLIC properties. Xenon is one of the inert or noble gases and is odorless, colorless, tasteless and chemically NON REACTIVE

PLEASE MARK BRAINLIEST

What is heat transferred from movement of fluids in a circular motion called

Answers

Answer: it's known as heat transfer

Explanation: Heat always moves from a warmer substance to a cooler substance. For example, holding an ice cube will make your hand begin to feel cold in a few seconds. But is the coldness in the ice cube moving to your hand? No! Since cold is the absence of heat, it’s the heat in your hand that moves to the ice cube. This is one of the ways that heat is transferred.

According to the concept of thermal energy, heat transfer in a circular motion is called as convection.

What is thermal energy?

Thermal energy is defined as a type of energy which is contained within a system which is responsible for temperature rise.Heat is a type of thermal energy.It is concerned with the first law of thermodynamics.

Thermal energy arises from friction and drag.It includes the internal energy or enthalpy of a body of matter and radiation.It is related to internal energy and heat .It arises when a substance whose molecules or atoms are vibrating faster.

These vibrating molecules and atoms collide and as a result of which heat is generated in a substance , more the collision of particles , higher is the thermal energy.There are three types of thermal energy.

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Which of these mixtures are heterogeneous? a. oil and water b. salt and water c. brass (an alloy of copper and zinc) d. granite

Answers

The mixture that has been heterogeneous has been oil and water. Thus, option A is correct.

The mixture has been defined as the combination of two or more substances. The mixture has been categorized as pure and heterogeneous mixture based on the solubility of the constituents.

Heterogeneous mixture

The pure mixture has been defined as the one in which the constituent substances are completely soluble, and are not visible with the bare eyes.

The heterogeneous mixture has been defined as the combination in which the constituents elements are not completely soluble and are easily differentiated from each other by physical means.

The mixture of oil and water has been a heterogeneous mixture, as the two liquids are immiscible and can be separated  based on density.

The salt and water is a pure mixture, as the two are completely soluble, and they can not be distinguished easily in the solution.

The brass is the pure mixture as they have properties different from the constituent elements and has been completely miscible form.

The granite has been a compound of carbon. It has been the mixture of carbon atoms in the specified arrangement, thereby is a pure form.

Thus, the mixture that has been heterogeneous has been oil and water. Thus, option A is correct.

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One way the U.S. Environmental Protection Agency (EPA) tests for chloride contaminants in water is by titrating a sample of silver nitrate solution. Any chloride anions in solution will combine with the silver cations to produce bright white silver chloride precipitate. Suppose an EPA chemist tests a 250 mL sample of groundwater known to be contaminated with nickel(II) chloride, which would react with silver nitrate solution like this: NiCl2 (aq) + 2AgNO3 (aq) -> 2AgCl (s) + Ni(NO3)2 (aq) The chemist adds 74.0 mM silver nitrate solution to the sample until silver chloride stops forming. She then washes, dries, and weighs the precipitate. She finds she has collected 8.3 of silver chloride. Calculate the concentration of nickel(II) chloride contaminant in the original groundwater sample. Show your work!

Answers

Answer:

15.0g/L is the concentration of nickel(II) chloride contaminant in the original groundwater sample.

Explanation:

Based on the reaction:

NiCl2 (aq) + 2AgNO3 (aq) -> 2AgCl (s) + Ni(NO3)2 (aq)

Where 1 mole of NiCl₂ reacts producing 2 moles of AgCl.

To solve this problem, we need to convert mass of AgCl to moles to know the moles of NiCl₂ that reacts. With these moles and the volume of the sample (250mL = 0.250L), we can determine the molar concentration of the contaminant in the sample

Moles AgCl:

8.3g of AgCl were collected. In moles (Molar mass AgCl: 143.32g/mol):

8.3g AgCl * (1mol / 143.32g) = 0.05791 moles AgCl

Moles NiCl₂:

As 2 moles of AgCl are produced from 1 mole of NiCl₂. Moles of NiCl₂ are:

0.05791 moles AgCl * (1 mole NiCl₂ / 2 moles AgCl) = 0.02896 moles NiCl₂

Molar concentration:

0.02896 moles NiCl₂ / 0.250L =

0.1158M

In g/L (Molar mass NiCl₂: 129.6g/mol):

0.1158 mol / L * (129.6g / mol) =

15.0g/L is the concentration of nickel(II) chloride contaminant in the original groundwater sample.

Please have your periodic table of elements. An atom has 8 protons and 9 neutrons what is the chemical symbol for this isotope? Question 9 options: Flourine F-17 Oxygen O-17

Answers

Answer:

A. is the answer i think

Explanation:

Which of the following is a property of a mixture?

Answers

Answer:

A mixture has 2 or more substances that are physically combined

Explanation:

Examples:

-Dirt and water (Mud)

-Water and salt (Sea water)

-Smoke and fog (Smog)

can someone help me please ??!!

Answers

Answer:

0.617

Explanation:

The experimental value is the average of all the values recorded:

(2.65 + 2.73 + 2.77)/3 = 2.72

Then use the equation:

(2.72 - 2.7)/ 2.7 x 100 = 0.617

Please Help with this!!!!!

Answers

Answer:

a) 4.69

Explanation:

v=mp

m=10.55

p=2.25

v=10.55/2.25=4.69

the answer is B-4.69

Magnesium exists in nature as three stable isotopes. Suppose you determine that 9.87 moles of natural magnesium are required if you wish to isolate 1.00 mole of pure Mg-25 (24.9858 amu). The most abundant isotope is Mg-24 with a mass of 23.9850 amu. Determine how many grams of the third isotope, Mg-26 (25.9826 amu), can be isolated from the 9.87 mole sample of natural magnesium.

Answers

Answer:  28.2 g of ²⁶Mg can be isolated from the 9.87 mole sample of natural magnesium

Explanation:

we know that natural abundance of ²⁶Mg is 11.01 %

therefore moles of ²⁶Mg isolated from 9.87 mole sample of natural magnesium will be :

( 11.01 x 9.87 mol) / 100  = 1.09 mol

so

mass of ²⁶Mg = mol x molar mass

⇒ 1.09 mol x 25.9826 g/mol

= 28.2 g

Therefore 28.2 g of ²⁶Mg can be isolated from the 9.87 mole sample of natural magnesium

Are the bonds that chlorine forms with sodium (to form NaCl) and with carbon (to form CCl4) the same in both compounds?

Answers

Answer:

Organic chemistry is very important to know the strength and forms of the compounds.

Explanation:

There are two extreme bonding that is ionic and covalent. There are some ionic bonds that contains the covalent bonding. Some of ionic bond are partially covalent and some covalent bond are ionic. Polar covalent have the extreme type of bonding.

Most of the carbon compound are bonded covalently. But these are partial ionic too. Polarity is defined as the measurement of the separation of the charges of the compounds at both the ends.

Ionic compounds allow synthesis in organic compound. Covalent bonds are differently important for carbon molecules bonding.

Thus the bonds that chlorine forms with sodium is different and when form with carbon then compounds will be different

What is potential energy? Give an example please.

Answers

Answer:

Potential energy can be defined as the energy in a body due to its position

In simple terms potential energy is the energy at rest

Explanation: Examples ;

A spring has more potential energy when it is compressed or stretched.A steel ball has more potential energy raised above the ground than it has after falling to Earth.

An element has four naturally occurring isotopes with the masses and natural abundances given here. Isotope Mass (amu) Abundance (%) 1 89.90470 52.93 2 90.90565 11.54 3 91.90504 17.65 4 93.90632 17.88 Find the atomic mass of the element. Express your answer to four significant figures and include the appropriate units.

Answers

Following are the calculation to the atomic mass:

Given:

Please find the attached file.

To find:

atomic mass=?

Solution:

Following are the calculation to the atomic mass:

[tex]\to 89.90470\times (0.5293)+90.90565\times (0.1154)+91.90504\times (0.1765)+93.90632\times (0.1788)\\\\\to 47.58655771 +10.49051201 +16.22123956+16.790450016\\\\\to 91.0887593\approx 91.0887\ amu \\\\[/tex]

Therefore, the final answer is "91.0887".

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Given six molecules, identify the molecules with polar bonds and the molecules that are polar.CCl4, CH3Cl, H20, CO2, O2

Answers

Answer:

Non-polar compounds: [tex]CCl_4[/tex], [tex]O_2[/tex], [tex]CO_2[/tex]

Polar compounds: [tex]CH_3Cl[/tex], [tex]H_2O[/tex]

Explanation:

For this question, we must start with the Lewis structure for each molecule and then we can do their respective analysis:

-) [tex]CCl_4[/tex]

In this case, we have 4 equal atoms attached to the central atom. Therefore, we have the same magnitude of electronegativity. Chlorine atoms have different and opposite directions. Therefore due to the orientation the dipole moments cancel and the net dipole moment will be zero and the molecule will be non-polar.

-) [tex]O_2[/tex]

In this case, we have a linear structure in which the magnitude of the dipole moment is the same, but the direction is the opposite. Therefore the dipole moments are canceled and the molecule will be non-polar.

-) [tex]CO_2[/tex]

In this case, we also have a linear structure in which the magnitude of the dipole moment is the same, but the direction is the opposite. Therefore the dipole moments are canceled and the molecule will be non-polar.

-) [tex]CH_3Cl[/tex]

For this molecule, we have a different atom. The hydrogen atom, therefore the magnitude of one of the atoms attached to the central atom is different and the magnitude of the net dipole moment will be different from zero and the molecule will be polar.

-) [tex]H_2O[/tex]

For this molecule, due to the structure of the molecule, the dipole moments of oxygens will not have a totally opposite configuration. Therefore, the net dipole moment will be different from zero and the molecule will be polar.

See figure 1 to further explanations

I hope it helps!

What is the role of the greenhouse gases in the atmosphere?

Answers

Answer:

greenhouse effects are molecules that trap heat on earth atmosphere

Answer:

play an important role in Earth's climate.

Explanation:

Greenhouse gases are certain molecules in the air that have the ability to trap heat in the Earth's atmosphere. Some greenhouse gases, like carbon dioxide (CO2) and methane (CH4), occur naturally and play an important role in Earth's climate. If they didn't exist, the planet would be a much colder place.

R spectroscopy can be used to identify which _____________________ are present in a compound.

Answers

Answer:

IR spectroscopy can be used to identify chemical structures are present in compounds.

Explanation:

Infrared spectroscopy is a technique in organic chemistry that can be use use to identify chemical structures present in compounds because it is base on the ability of different functional groups to adsorb infrared light.

This work by shinning the infrared lights into the organic compounds to be identified, some of the frequencies of the infrared lights are adsorbed by the compounds and its identify groups of atoms and molecules in the compound.

Glve the number of significant figures: 13,436.0 mm
Significant figures:

Answers

Answer: 6

Explanation: Because there is a decimal point, the zero after is included. The first 5 numbers are significant because they aren’t zero. Zeros are included if there is a decimal point (13.0, 160.0) or are in the middle of a number (16007, 101). They are not included if they are before a decimal (000.0081, 0.000021)-(there are only 2 sig figs in these: the actual numbers) or after a number without a decimal (15840000, 100)-(all the zeros in these numbers are not significant).

Which of the following compounds is neither an acid or a base? (select as many)

Answers

Answer:

Sodium nitrate and CH4

Explanation:

Acids have an "H" at the start and bases have a hydroxide (OH)

Write a balanced equation for the neutralization of hydrochloric acid by barium hydroxide. Use the smallest possible integer coefficients.

Answers

Answer:

2HCl + Ba(OH)2 = BaCl2 + 2H2O

Explanation:

To solve such this we must know the concept of  neutralization reactions. Therefore, the  balanced equation for the neutralization of hydrochloric acid by barium hydroxide is 2HCl + Ba(OH)[tex]_2[/tex] [tex]\rightarrow[/tex] BaCl[tex]_2[/tex] + 2H[tex]_2[/tex]O.

What is chemical reaction?

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.

Neutralization is an acid-base reaction in which an acid reacts with just a base to produce salt and water. The pH of a neutralizing solution is determined by the acid strength and concentrations of the reactants. The balanced equation for neutralization of hydrochloric acid by barium hydroxide can be written as

2HCl + Ba(OH)[tex]_2[/tex] [tex]\rightarrow[/tex] BaCl[tex]_2[/tex] + 2H[tex]_2[/tex]O

Therefore, the balanced equation for the neutralization of hydrochloric acid by barium hydroxide is 2HCl + Ba(OH)[tex]_2[/tex] [tex]\rightarrow[/tex] BaCl[tex]_2[/tex] + 2H[tex]_2[/tex]O.

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Which of the following statements best explains the observation that hydrogen fluoride has the highest boiling point of all the hydrogen halides?a. The fluorine in HF is the smallest atom for all of the halogens. b. Fluorine is the most electronegative of the atoms. c. HF can participate in hydrogen bonding. d. HF is very reactive and can react and dissolve glass e. HF is a weak acid, and doesn

Answers

Answer:

c. HF can participate in hydrogen bonding.

Explanation:

The boiling points of substances  often reflect the strength of the intermolecular forces operating among the molecules.

If it takes more energy to  separate molecules of HF than of the rest of the hydrogen halides because HF molecules are held  together by stronger intermolecular forces, then the boiling point of HF will be higher than  that of all the hydrogen halides.

A particularly strong  type of intermolecular attraction is called the hydrogen bond, which is a special type of dipole-dipole interaction between the hydrogen atom in a polar bond, such as N-H, O-H, or F-H, and an electronegative O, N, or F atom.

Identify all of the predominant forms of energy produced when each process occurs. Some processes may produce only one form of energy, whereas others may produce more than one form of energy. An electric light bulb is turned on. A log is burned in a fireplace. Answer Bank mechanical thermal cheat) electrical radiant light) chemical A green plant grows. A bicycle is pedaled. A flashlight is turned on.

Answers

Answer:

Explanation:

An electric light bulb is turned on.   Thermal heat , radiant light

A log is burned in a fireplace .  Thermal heat        , radiant light

A green plant grows  Chemical

A bicycle is pedaled  Mechanical ,

A flashlight is turned on.   radiant light

True or False? If a substance is mixed with another substance and then the result is a new odor, then is reaction is a physical reaction.

Answers

Answer:

True

Explanation:

In a chemical reaction, there's usually something to do with the composition of the substance. In a physical reaction, the effect could have something to do with appearance or smell.

Hope this helps!

How can you use the number of electrons in an aluminum atom to determine how many protons and neutrons are in its nucleus?

Answers

Answer:

You use the number of electrons in an aluminum atom to determine how many protons are in its nucleus because the atomic number of aluminum, 13, tells you how many electrons and protons they are. Then you can the  number of neutrons by subtract it's atomic number by its mass, 27, which will result in the number of neutrons, 14.

Explanation:

The atomic number of aluminum is 13 and mass number of aluminum is 27. This helps us to tell us how many protons, electrons and neutrons are there in its nucleus.

What is atomic number?

The atomic number of a chemical element  is defined as the charge number of an atomic nuclei.

The mass number of an atom tells us the number of protons and neutrons are there in an atoms.

The number of electron surrounding the nucleus is equal to number of protons present in the nucleus. Hence there is 13 electrons  and 13 protons in the nucleus.

Now we can calculate number of neutrons present in the nucleus.

Mass number = number of protons + number of neutrons

Number of neutrons = mass number - number of protons

                                   = 27 - 13 = 14

So number of neutrons is 14 , and  number of protons is 13.

Thus, atomic number of aluminum is 13 and mass number of aluminum is 27. This helps us to tell us how many protons, electrons and neutrons are there in its nucleus.

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Now balance the chemical reaction by providing the correct coefficients:

Answers

Answer: 2 Al + 3 Cl₂ → 2 AlCl₃

Explanation:

To balance equations, you want to have the same amount of each element. We know 2 Al + 3 Cl₂ → 2 AlCl₃ is the balanced equation because there are equal amounts of each element on both sides. There are 2 Al and 6 Cl.

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