Find the number of CO2 molecules present in 20l of CO2 at 0°C and 772mm of Hg.
I wiLL mark you as brainliest and give 50 points.
Answer:
18
At STP, 22.4 liters of a gas forms one mole that is 6.023×10
23
molecules.
Volume of CO
2
in 1 litre of air =
100
0.03
×1 L
∴ No. of molecules of CO
2
=
22.4
6.023×10
23
×
100
0.03
=8.066×10
18
Explanation:
I guess it's this
[tex]\\ \sf\longmapsto PV=nRT[/tex]
[tex]\\ \sf\longmapsto n=\dfrac{PV}{RT}[/tex]
[tex]\\ \sf\longmapsto n=\dfrac{772(20)}{8.314(273)}[/tex]
[tex]\\ \sf\longmapsto n=\dfrac{15440}{2269.722}[/tex]
[tex]\\ \sf\longmapsto n=6.8mol[/tex]
A car starts from rest and accelerates at 2.5m/s^2 for 2s. What is the final velocity of the car
[tex]\begin{gathered}\boxed{\begin{array}{c}\\ {\pmb{\sf{Three \: equation \: of \: motion}}} \\ \\ \sf \star \: v \: = u \: + at \\ \\ \sf \star \: s \: = ut + \: \dfrac{1}{2} \: at^2 \\ \\ \sf \star \: v^2 - u^2 \: = 2as\end{array}}\end{gathered}[/tex]
Calculation :-[tex]\pink{\qquad \pmb{ \sf\longrightarrow v \: = u \: + at}}[/tex]
[tex] \qquad \pmb{\sf \longrightarrow v = 0 + 2.5 \times 2}[/tex]
[tex]\qquad \pmb{ \sf\longrightarrow v = 0 + 5}[/tex]
[tex] \qquad \pmb{\sf \longrightarrow v = 5 \: ms^{-1}}[/tex]
[tex]\qquad \longrightarrow {\pink{\underline{\underline{\pmb{\sf{ Final \: velocity= 5 \: ms^{-1} }}}}}}[/tex]
Henceforth –
The final velocity of the car is 5 m/s▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬
What volume does 0.25 moles of oxygen gas occupy at STP ?
Answer:
[tex]\boxed {\boxed {\sf 5.6 \ L \ O_2}}[/tex]
Explanation:
We are asked to find the volume of 0.25 moles of oxygen gas.
At standard temperature and pressure or STP, one mole of any gas has a volume of 22.4 liters.
We want to convert 0.25 moles of oxygen gas or O₂ to liters. We will use dimensional analysis, so we must set up a conversion factor.
[tex]\frac {22.4 \ L \ O_2}{1 \ mol \ O_2}[/tex]
We are converting 0.25 moles of oxygen gas, so we multiply the conversion factor by this value.
[tex]0.25 \ mol \ O_2 *\frac {22.4 \ L \ O_2}{1 \ mol \ O_2}[/tex]
The units of moles of oxygen gas cancel.
[tex]0.25 *\frac {22.4 \ L \ O_2}{1 }}[/tex]
[tex]0.25 * 22.4 \ L \ O_2[/tex]
[tex]5.6 \ L \ O_2[/tex]
0.25 moles of oxygen gas occupy 5.6 liters at standard temperature and pressure.
What has more atoms, a mole of carbon or a mole of fluorine?
A mole of carbon
A mole of Florine
They have the same number of atoms
Answer:
They have the same number of atoms
Explanation:
The mole (symbol: mol) is the base unit of amount of substance.
Think of mole meaning like inch. An inch of grass is the same as an inch of a flower. Mole is the standard measuring unit of atoms.
The diagram shows fertilization, the union of sperm cell and egg cell.
The traits of the offspring of the fertilized egg are coded onto
A
lipids in the offspring's cell membranes.
B
enzymes in the offspring's ribosomes.
C
genes in the offspring's chromosomes.
D
water in the offspring's mitochondrion.
Chemistry help!!
A student conducts an experiment to separate water into hydrogen and oxygen as shown below.
As a result the student collects 28.0 g of hydrogen and 224.0 g of oxygen. How many grams water did the student originally have involved in the experiment
The student originally has 252 grams of water in this experiment.
LAW OF CONSERVATION OF MASS:
The law of conservation of mass explains that matter (mass) can neither be created nor destroyed but can be changed from one form to another. This means that in a chemical reaction, the sum of the masses of the reactants must equate to the total mass of product(s). According to this question, a student conducts an experiment to separate water into hydrogen and oxygen. The student collects 28.0 g of hydrogen and 224.0 g of oxygen. Since hydrogen and oxygen are the constituent elements of water, the sum of their masses must equate the mass of water. Therefore, 224g of oxygen + 28g of hydrogen = 252g of water.Learn more at: https://brainly.com/question/24996173?referrer=searchResults
Please help? It’s for chem
Answer:
O-H
Explanation:
It is polar covalent bond, because the hydrogen atom has electronegativity about 2.6, and the oxygen atom, electronegativity about 3.6. When the difference in electronegativity of the atoms is between 0.4 and 1.7, the result is a polar covalent bond.
Which of these elements would have an electron affinity higher than that of oxygen?
Li
Ca
Ne
C
Be
Answer: Ne ( Neon )
Explanation: Lithium ( Li ), beryllium ( Be ), carbon ( C ), oxygen ( O ), and neon ( Ne ), are all in Period 2 in that order. Sodium ( Na ) is in Period 3. Since electron affinities decrease as you go down, Na would have a lower electron affinity level then Li but since electron affinities increase as you go across a period, only neon is farther right then oxygen ( O ), so it would be the only one element of this group that would have a higher electron affinity than that of oxygen.
There are various kind of elements that are present in periodic table. Some elements are harmful, some are radioactive, some are noble gases. Option C is correct option.
What is periodic table?Periodic table is a table in which we find elements with properties like metals, non metals, metalloids and radioactive element arranges in increasing atomic number.
Periodic table help a scientist to know what are the different types of elements are present in periodic table so that they can discover the new elements that are not being discovered yet.
On going down the group electronegativity decreases. On going along the period the electronegativity increases. So, Neon lies on the extreme right of Fluorine in the same period. Neon will have more electronegativity than oxygen.
Therefore, Neon is more electronegativity than fluorine.
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what makes your pulse? Explain
PLEASE HELP WILL MARK BRAINLIEST
Answer:
the answer is 150 in centimeters
put these atoms in order of increasing radius: Na, Mg,Cl, P
Answer:
Cl < P < Mg < Na
Explanation:
Cl must have the smallest radius because it is located to the right of the remaining elements on the same row. P must have the second smallest radius because it is located to the right of the remaining elements on the same row. Mg must have the Third smallest radius because it is located to the right of Na on the same row. Therefore, Na has the Largest radius.
I hope it helps.
How to find formula for ionic compounds.
Answer:
I am using an example for this in this table it works for any other compound as well.
under the same conditions of temperature and pressure how does a liquid differ from a gas
A solution containing cacl2 is mixed with a solution of li2c2o4 to form a solution that is 2. 1*10^-5m in calcium ion and 4. 75*10-5 m in oxalate ion. What will happen once these solutions are mixed?\.
Answer:
the answer is d
Explanation:
i know
mr. garcia uses magnets to hold a poster on a steel filing cabinet because a main component of steel is iron. carbon. plastic. glass.
Mr. garcia uses magnets to hold a poster on a steel filing cabinet because a main component of steel is iron.
What is iron?The chemical element iron has the atomic number 26 and the symbol Fe. It is a metal that is found in group 8 of a periodic table and the first transition series. It makes up a large portion of the planet's outer or inner core and is the most prevalent element on Earth by mass, just ahead of oxygen.
It is the fourth most prevalent element in the crust of the Earth, having been mostly deposited by meteorites inside its metallic state, along with its ores. Iron ores must be processed in kilns or furnaces that may reach 5000 °C (2,730 °F) and higher, which is approximately 500 °C (932 °F) greater than the temperature needed to smelt copper. Mr. garcia uses magnets to hold a poster on a steel filing cabinet because a main component of steel is iron.
Therefore, mr. garcia uses magnets to hold a poster on a steel filing cabinet because a main component of steel is iron.
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measuring the isotopic composition of atmospheric co2 shows that the burning of fossil fuels has led to _____ co2 levels over the last 200 years.
Answer:
measuring the isotopic composition of atmospheric co2 shows that the burning of fossil fuels has led to the co2 levels over the last 200 years.
Explanation:
pa brainliest po ty
what is the name of the high-energy compound that cells use to fuel chemical reactions?
Answer: Adenosine triphosphate, or ATP, is the primary carrier of energy in cells. The water-mediated reaction known as hydrolysis releases energy from the chemical bonds in ATP to fuel cellular processes.
Explanation:
An element Argon has atomic number 18. Deduce the electronic configuration of the elements and suggest the group to which this element belong.
Answer:
8th or 0th group known as Noble gases
An atom of sodium has 11 electrons. Make a sketch of a sodium atom, showing how many electrons it has at each energy level. Infer how reactive sodium atoms are.
SOMEONE HELP ME PLEASE :(. I DONT GET IT :(
how can teh human body looose heat? (conduction, convecion, radiation) and WHY
Answer:
Radiation and conduction
Explanation:
The human body lose heat by these two ways, because everything that touches our bodies and is in a temperature below us will receive part of our heat (conduction), and you can figure out that we lose heat by radiation because a human bright in a heat cam
How do mixtures differ from substances?
Answer:
In chemistry: a pure substance consists only of one element or one compound. a mixture consists of two or more different substances, not chemically joined together.
Hope this helps :)
Give 2 reason why cryolite is used
Describe how the suspects used the chemicals found at the crime scene to make the copper coins look silver.
The chemicals found at the crime scene although not mentioned must be Sodium zincate.
Discussion:
An interesting demonstration to show plating and alloys is the conversion of copper coins to silver look-alike coins.
A 'copper' coin when dipped into a solution of sodium zincate in contact with zinc. The coin is plated with zinc and appears silver in colour.
This is a common chemistry classroom trick.
Read more on plating:
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Help ASAP!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!:)
Correct:
Delivers Nutrients to cells Removes waste materials from cellsProtects the body from pathogensHelps cuts and wound to heal.Incorrect:
Brings carbon dioxide to cells for use.Carbon dioxide is the waste product of cells that you let out each time you breathe.
¿Cuáles son las características que presentan las enzimas? Explica cada una
Answer:
Acelera las reacciones químicas.
Se requieren en cantidades mínimas.
Son muy específicos en su acción.
Se ven afectados por la temperatura.
Se ven afectados por el pH.
Algunos catalizan reacciones reversibles.
Algunos requieren coenzimas.
Son inhibidos por inhibidores.
Explanation:
determine the element of lowest atomic number that contains a complete d subshell in the ground state.
Answer:
The element with the lowest atomic number that contains a complete d-subshell in the ground state is copper.Source:
Determine the element of lowest atomic number that contains a complete d subshell in the ground... - Study.comWhy doesn’t one-electron transfer from a hydrogen atom to another hydrogen atom?
Answer:
The electrons start to repel each other.
Explanation:
Most atoms attain a lower potential energy when they are bonded to other atoms than when they are separated. One is that the single electrons that each hydrogen atom possesses begin to repel each other. This repulsive force would tend to make the potential energy of the system increase.
Violet light has a wavelength from 380 nm to 420 nm.
What velocity must a free electron have in order to exhibit the same wavelength as a violet photon with a
wavelength of 415 nm?
This question involves the concepts of de Broglie's wavelength and momentum.
The velocity of the electron must be "1754.27 m/s".
de Broglie's wavelength is a wavelength associated with a moving matter particle. It is connected to the momentum of the particle by the following formula:
[tex]P =\frac{h}{\lambda}\\\\mv=\frac{h}{\lambda}\\\\v=\frac{h}{m\lambda}\\\\[/tex]
where,
v = velocity of electron = ?
h = Plamk's Constant = 6.625 x 10⁻³⁴ J.s
m = mass of electron = 9.1 x 10⁻³¹ kg
λ = de Broglie's wavelength = 415 nm = 4.15 x 10⁻⁷ m
Therefrore,
[tex]v=\frac{6.625\ x\ 10^{-34}\ J.s}{(9.1\ x\ 10^{-31}\ kg)(4.15\ x\ 10^{-7}\ m)}[/tex]
v = 1754.27 m/s
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type the max number of electrons that can be present in each shell or sub below
n = 5 shell __
n = 2 shell __
n = 2 l = 0 sub: __
n = 2 / 1 sub: __
3d sub: __
2s sub: __
5f sub: __
Explanation:
The maximum no. of electrons in a shell is given by. 2n^2 .
So for
n= 5 , 2× 5× 5 = 50
n=2 , 2×2×2 = 8
For a sub shell the maximum no. of electrons possible is given by 2(2l + 1)
So for n= l= 0
2 [(2×0) +1] = 2
for n=2 l=1
2 [(2×1) + 1] = 6
3d
d sub shell has l= 2 quantum number
Therefore 2[ (2×2) + 1] = 10
2s
s sub shell has l=0 quantum number
2 [(2×0) +1] = 2
5f
f sub energy level has l=3 quantum number
So 2[ (2×3) +1 ] = 14
The azimuthal quantum numbers for the sub shells are as follows
( s ---> 0
p----> 1
d----> 2
f ----> 3 )
Which is the formula for nitrogen trihydride? NH3 N3H 3NH N3H3
the answer isssssssssssssssssssssss... Nh3.
Answer: A.) NH3
Explanation:
