Answer:
Left
Explanation:
To convert from Nanograms to centigrams, you have to move the decimal to the left hand side.
1 nanograms = 1 x 10⁻⁹g
1 centigrams = 1 x 10⁻² g
So to convert from nanograms to centigrams,
Multiply by 1 x 10⁻⁷ or move 7 places to the left
The initial volume of a gas cylinder is 750 ml if the pressure of a gas inside the cylinder changes from 840 mm hg to 360 mm hg
Answer:
V₂ = 1750 mL
Explanation:
Given data:
Initial volume = 750 mL
Initial pressure = 840 mmHg
Final pressure = 360 mmHg
Final volume = ?
Solution:
The given problem will be solved through the Boly's law,
"The volume of given amount of gas is inversely proportional to its pressure by keeping the temperature and number of moles constant"
Mathematical expression:
P₁V₁ = P₂V₂
P₁ = Initial pressure
V₁ = initial volume
P₂ = final pressure
V₂ = final volume
Now we will put the values in formula,
P₁V₁ = P₂V₂
840 mmHg × 750 mL = 360 mmHg × V₂
V₂ = 630,000 mmHg.mL/360 mmHg
V₂ = 1750 mL
In a mixture of hydrogen and helium gases, the mole fraction of helium is 0.750. If the partial pressure of hydrogen in the mixture is 75 torr, what is the total pressure of the mixture?a. 100 torr b. 300 torr c. 19 torr d. 750 tor e. 760 torr
If the partial pressure of hydrogen in the mixture is 75 torr, the total pressure of the mixture is 100 torr.
What is partial pressure?Partial pressure is the notional pressure present in every gas.
Given,
The mole fraction of helium is 0.750.
The partial pressure of hydrogen in the mixture is 75 torr
The mole fraction of hydrogen is
To find the total pressure
By Roult's law
Partial pressures divided by mole fraction
75 / 0.750 = 100 torr
Thus, the correct option is a, 100 torr.
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An electrochemical cell is composed of pure nickel and pure iron electrodes immersed in solutions of their divalent ions at room temperature (25°C). If the concentrations of Ni2+ and Fe2+ ions are 0.002 M and 0.40 M, respectively, what voltage is generated at 25°C? (The respective standard reduction potentials for Ni and Fe are −0.250 V and −0.440 V.)
Answer:
0.758 V.
Explanation:
Hello!
In this case, case when we include the effect of concentration on an electrochemical cell, we need to consider the Nerst equation at 25 °C:
[tex]E=E\°-\frac{0.0591}{n} log(Q)[/tex]
Whereas n stands for the number of moles of transferred electrons and Q the reaction quotient relating the concentration of the oxidized species over the concentration of the reduced species. In such a way, we can write the undergoing half-reactions in the cell, considering the iron's one is reversed because it has the most positive standard potential so it tends to reduction:
[tex]Fe^{2+}+2e^-\rightarrow Fe^0\ \ \ E\°=0.440V\\\\Ni^0\rightarrow Ni^{2+}+2e^-\ \ \ E\°=-0.250V[/tex]
It means that the concentration of the oxidized species is 0.002 M (that of nickel), that of the reduced species is 0.40 M and there are two moles of transferred electrons; therefore, the generated potential turns out:
[tex]E=(0.440V+0.250V)-\frac{0.0591}{2} log(\frac{0.002M}{0.40M} )\\\\E=0.758V[/tex]
Beat regards!
Why is the area called the Fertile Crescent?
Answer:
the soil is very fertile
Explanation:
When you bite into an apple, your teeth act as which type of simple machine?
Answer:
Lever.
Hope this helps!
Explanation:
Answer:
Wedge
Explanation:
The simple machine that SPLITS the apple when you bite into it is a wedge.
a b c or d? help asap
Answer:
A. No, they were growing not developing.
Explanation:
The equation K + NaOH => Na + KOH should it react, true or false?
Answer:
yes it should react yoyoyoyoyo
To show the electron configuration for an atom, when would it be better to use an orbital notation than to use a written configuration with numbers, letters, and superscripts? when the aim is to use less space when the aim is to show electron spins when the aim is to show orbital shapes in subshells when the aim is to show electron distributions in shells
Answer:
D-when the aim is to show electron distributions in shells
Explanation:
Answer:
D on edge 2021
Si2Br6 compound name
Answer:
disilicon hexabromide
Explanation:
Which of the following statements is true?
The buildup of carbon dioxide in the atmosphere causes the greenhouse effect.
An increase in pressure causes an increase in reaction rate.
The formation of gas bubbles is an indication of a chemical change.
all of the above
Answer:
is there an all of them are true option cause it should be that
Explanation:
your answer to your question is all of the above
What action is NOT necessary before lighting a Bunsen burner?
A)Make sure there are no holes in the hose connected to the burner.
B)Leave the gas stop open for a few minutes before lighting to clear the line.
C)Clear the burner area of flammable materials such as solvents and papers.
D)Check that the gas regulator and air inlet on the burner can be adjusted.
Answer:
the answer is opetuon B
The Bunsen burner is a heating apparatus used to heat samples in the laboratory. The correct answer is option B: )Leave the gas stop open for a few minutes before lighting to clear the line.
A Bunsen burner is commonly used as a heating apparatus. It contains a gas that can be controlled using a gas regulator.
It is necessary to do the following before lighting the Bunsen burner;
Make sure there are no holes in the hose connected to the burner.Clear the burner area of flammable materials such as solvents and papers.Check that the gas regulator and air inlet on the burner can be adjusted.So, it is not necessary to Leave the gas stop open for a few minutes before lighting to clear the line before lighting a Bunsen burner.
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Which compound is a polar molecule and has a linear geometry
Answer:
Linear molecule is a molecule in which atoms are deployed in a straight line (under 180° angle). Molecules with an linear electron pair geometries have sp hybridization at the central atom. An example of linear electron pair and molecular geometry are carbon dioxide (O=C=O) and beryllium hydride BeH2.
Explanation:
Lack of employment and income opportunities are pushing large contingents of people to frontier areas and new economic activities, such as gold mining, in the Amazonian region. The number of independent gold miners exceeded 200,000 by 1990. The mining process generates very dangerous and poisonous mercury pollution (mercury is used to separate the gold from other materials), and destroys aquatic and forest habitats. The local population whose diet depends on fish are now threatened by mercury poisoning, as are the miners themselves. –United Nations Research Institute for Social Development Read the text, then use the drop-down menus to complete the statements. People have turned to gold mining because of a lack of opportunities. The is dangerous because it generates mercury .
Answer:
1. employment 2. mining process 3. pollution
Explanation:
I took the assignment, it is 100% correct. : )
Answer:
B
Explanation:
increased pollution
what is the source of iodine
Answer:
salt.
Explanation:
Mark me as brainliest
How would the number of oxygen atoms in a 16.00 pound sample compare to the number of sulfur atoms in a 32 pound sample?
The force that holds protons together is called...?
Answer: Answer is in Explanation
Explanation:
The strong nuclear force pulls together protons and neutrons in the nucleus. At very small distances only, such as those inside the nucleus, this strong force overcomes the electromagnetic force, and prevents the electrical repulsion of protons from blowing the nucleus apart.
What would change oxygen into another isotope
Answer:
Adding Neutrons
General Formulas and Concepts:
Chemistry - Atomic Structure
Atoms CompositionNucleus - Protons, NeutronsElectronsExplanation:
We know that adding Protons to any atom will change its chemical properties and make it a different element.
We also know that adding Electrons to any atom will simply only change its overall charge.
Isotopes are formed by adding neutrons to the nucleus. It will be the same element but it would have a different mass and amount of neutrons.
Question 23 of 25
Which of these is a disadvantage of using natural gas?
A. It is not considered safe to use in homes.
B. It burns less cleanly than other fossil fuels.
C. Scientists have developed new ways of extracting it.
D. Extraction through fracking can contaminate groundwater.
SUBMIT
Answer:
the answer is D. extraction through fracking can contaminate groundwater
The disadvantage of natural gas has been the contaminating groundwater due to fracking. Thus, option D is correct.
Natural gas has been the stored fossil energy that has been found buried deep inside the earth. The gas has consisted of a varying quantity of compounds with a maximum proportion of methane.
Natural gas has been nonrenewable, causing pollution with the burning. The release of greenhouse gases with the burning of natural gas results in affecting the environment.
Although there has been the presence of various extraction methods, natural gas results in contaminating groundwater due to fracking. Thus, option D is correct.
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WILL GET BRAINLIEST AND LOTS OF POINTS IF YOU ANSWER CORRECTLY W EVIDENCE (QUESTION IN PIC BELOW)
Answer:
element,compound
Explanation:
im petty sure this is the anwser
Answer: D
Explanation:
The normal boiling point of mercury (Hg) is 356.7 °C. What is the vapor pressure of mercury at 333 °C in atm? (∆Hvap = 58.51 kJ/mol
Answer:
Here you can use the Clausis Clayperon equation: ln P1/P2=-Ea/R-(1/T1 - 1/T2)
where P1 is the pressure at standard condition: 760 mm Hg
P2 is the variable we need to solve
Ea is the activation energy, which in this case is delta H vaporisation: 56.9 kJ/mol
R is the gas constant 8.314 J/mol or 8.314 J/mol /1000 to convert to kJ
T1 is the normal boiling point 356.7 C, but converted to Kelvin: 629.85K
T2 is room temperature 25 C, but converted to Kelvin: 298.15 K
Once you plug everything in, you should get 4.29*10^-3 mmHg
Explanation:
Purple flowers are dominant over white flowers. The parent generation includes two heterozygous parents. What are the possible phenotypes of these parents’ offspring? 3 purple and 1 white 3 white and 1 purple 1 purple, 2 lilac, and 1 white 1 white, 2 speckled, 1 purple
A. 3 purple and 1 white. :)
answer on EDGE2020. took/taking the exam.
Purple flowers are dominant over white flowers. The parent generation includes two heterozygous parents. The possible phenotypes of these parents’ offspring are 3 purple and 1 white. Therefore, option A is correct.
What do you mean by phenotype ?A person's genotype is their unique DNA sequence. This term is used to refer to the two alleles that a person inherited for a specific gene. A patient's clinical presentation is the detectable expression of this genotype.
We have three phenotypic classes with one locus and additive effects: AA, Aa, and aa.
Height, wing length, and hair color are all phenotypes. Phenotypes also include observable characteristics that can be measured in the lab, such as hormone levels or blood cell counts.
Purple flowers outnumber white flowers. There are two heterozygous parents in the parent generation. These parents' offspring could have three purple phenotypes and one white phenotype.
Thus, option A is correct.
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What occurs during a solar elcipse
Answer:
the moon gets infront of the sun
Answer:
A solar eclipse happens when the moon moves in front of the Sun as seen from a location on Earth. During a solar eclipse, it gets dimer and dimmer outside as more and more of the Sun is covered by the Moon. During a total eclipse, the entire Sun is covered for a few minutes and it becomes very dark outside. The temperature outside also drops.
Theo mixes cake batter and places it in the oven at 350°F for 45 minutes. Explain what type of reaction baking a cake represents in terms of energy
Answer:
Baking a cake requires heat to be applied to the batter in order for it to cook and chemically change into cake. The energy or heat applied is absorbed by the ingredients, so this represents an endothermic reaction.
Explanation:
Answer:
Sample Response: Baking a cake requires heat to be applied to the batter in order for it to cook and chemically change into cake. The energy or heat applied is absorbed by the ingredients, so this represents an endothermic reaction.
Explanation:
on edge
Please Help. A car was sitting in sunlight all day long.The heat that is now contained in the car was transferred to the car primarily by which of the following processes?
A. Radiation
B. Conduction
C. Convection
D. Electrical energy transfer
Answer: A
Explanation:
The heat contained in the car was transferred to the car primarily by the process of radiation.
Radiation is the emission of electromagnetic wave energy that originates from a source and travels via a space medium with the speed of light. When it is sunny during the day, all life forms and inanimate objects are exposed to radiation. Since a car has metallic properties, it has the ability to store and contain the heat for a longer period of time through the process known as radiation.
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The vertical axis of a graph shows the
Answer:
The horizontal axis represents years and the vertical axis represents units of sales. The graph presents both the increase and decline in sales for both products, as sales fluctuated during the ten-year period.
Explanation:
QUESTION 3
Acids should be stored in which type of glass?
What is the wavelength of a photon that has 4.42 x 10^8 of energy?
Answer:
λ = 4.5×10⁻³⁴ m
Explanation:
Given data:
Energy of photon = 4.42×10⁸ J
Wavelength of photon = ?
Solution:
Formula:
E = hc/λ
speed of light = c = 3×10⁸ m/s
planck's constant = h = 6.63×10⁻³⁴ Js
Now we will put the values in formula.
4.42×10⁸ J = 6.63×10⁻³⁴ Js × 3×10⁸ m/s / λ
λ = 6.63×10⁻³⁴ Js × 3×10⁸ m/s / 4.42×10⁸ J
λ = 19.89×10⁻²⁶ Jm / 4.42×10⁸ J
λ = 4.5×10⁻³⁴ m
1.
Examine the molecule SF4 in the Real Molecules screen to check your prediction from
question c. Which interactions are more important in determining where the lone pair
will go?
Answer:
See explanation
Explanation:
In SF4, the lone pair is placed at an equatorial position. One needs to consider the A-B interactions (axial-equatorial) as well as the B-B (equatorial-equatorial) interactions.
The lone pair occupies an equatorial site to minimize repulsion and maximize the space between electron pairs. Remember that equatorial bonds(Xeq-E-Xeq) are at an angle of 120 degrees while axial bonds(Xax-E-Xeq) lie at an angle of 90 degrees.
It should be noted that in the molecule SF4, the lone pair is placed at an equatorial position.
From the complete question, it's important to consider the axial-equatorial interactions as well as the equatorial-equatorial which is the B-B interactions.
Furthermore, the lone pair occupies an equatorial site that is vital in minimizing repulsion as well as maximizing the space that's between the electron pairs.
In conclusion, the lone pair is placed at an equatorial position.
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20 POINTS + BRAINLIEST, HELP
Explain how electron microscopes work and why some scientists might prefer to use electron microscopes instead of light microscopes.
Answer:
Electron microscopes differ from light microscopes in that they produce an image of a specimen by using a beam of electrons rather than a beam of light. Electrons have much a shorter wavelength than visible light, and this allows electron microscopes to produce higher-resolution images than standard light microscopes.
Explanation: