What is the empirical formula of a compound composed of 72.36% Fe and 27.64% O by mass?
empirical formula:
Answer:
Empirical formula = Fe₃O₄
Explanation:
Given data:
Percentage of Fe = 72.36%
Percentage of oxygen = 27.64%
Empirical formula = ?
Solution:
Number of gram atoms of O = 27.64 / 16 = 1.7
Number of gram atoms of Fe = 72.36 / 55.8 = 1.3
Atomic ratio:
Fe : O
1.3/1.3 : 1.7/1.3
1 : 1.3
Fe : O = 1 : 1.3
Empirical formula = 3( 1: 1.3)
Empirical formula = Fe₃O₄
1. At STP, potassium is classified as
A. a metallic solid
B.a nonmetallic solid
C.a metallic liquid
D. metalloid solid
There are 285 mL in a cup of tea. What is the volume in liters?
Answer:
0.285 L
Explanation:
285ml divided by 1000=0.285L
The number of mitochondria in an animal cell varies. Mitochondria are found more in active cells like liver and less in hair cells. Which phrase best explains the role of mitochondria in the active cells?
Group of answer choices
remove waste products from the cell
make high energy molecules for the cell to function
contain information to start a cell division
control movement of material in and out of the cell
Answer:
Make high energy molecules for the cell to function.
Explanation:
Remember mitochondria is the storehouse of the cell.
Hope it helps!
assuming nitrogen behaves like an ideal gas, what volume would 14.0 g of nitrogen gas (N2) occupy at STP? the gas constant is 0.0821 Lxatm/kxmol
Answer:
V = 22.41 L
Explanation:
Given data:
Mass of nitrogen = 14.0 g
Volume of gas at STP = ?
Gas constant = 0.0821 atm.L/mol.K
Solution:
Number of moles of gas:
Number of moles = mass/molar mass
Number of moles= 14 g/ 14 g/mol
Number of moles = 1 mol
Volume of gas:
PV = nRT
1 atm × V = 1 mol × 0.0821 atm.L/mol.K × 273 K
V = 22.41 atm.L / 1 atm
V = 22.41 L
Drops of a clear liquid are added to a red liquid. As the drops are added, the red liquid
becomes orange, then yellow. Which of the following is an indicator that a chemical
reaction occurred?
A. Formation of a precipitate
B. Emission of light
C. Color Change
D. Gas formation
Answer:
B. Color change
3&5
hope this helps <3
have a great day/night
-Dan
can somebody give me the answer to this ?
Answer:
burning paper
Explanation:
i think its burning paper.
Answer:
That`s tough for me to answer, but the definition is to retain, or require heat or energy to make a function of process. I would think it is fireworks, because a chemical reaction is required to produce the effects, but each answer retains heat in some way. I would still choose fireworks though. Hope that helps . . .
Which of the following elements should have properties similar to those of nitrogen
Answer:
Nitrogen group element, any of the chemical elements that constitute Group 15 (Va) of the periodic table. The group consists of nitrogen (N), phosphorus (P), arsenic (As), antimony (Sb), bismuth (Bi), and moscovium (Mc)
Explanation: Hope i helped! :D
1. A gas has a volume of 6.0L, a temperature of 402K, and there are 3.98moles.
What is the pressure? (R = 0.0821 L*atm/mol*K)
Answer:
The pressure should be 21 atm. You can change units if needed
Explanation:
use the forumla PV=nRT. To figure out pressure you need to divide by the volume on each side. the put the apporite units into the formula and Bam. u got it
List Earth’s four spheres.
Will give out free Brainiest
Answer:
The four spheres of it are,
Explanation:
1. Lithosphere
2. Atmosphere
3. Biosphere
4. Hydromasphere
May It's Help U
Which among these were independent
variables?
Amount of sunlight
Amount of water
Amount of fertilizer
Plant growth
2. Create three questions that could be answered after doing this lab activity. Be sure
to include the answers!
what will happen of sodium and water react(be careful)
make slime
make chapathi and paneer butter masala
Which statement is not true about constitutional isomers?
Answer: They always have the same functional groups.
Explanation:
use quizlet too if you have toooo
Answer:
they have same physical properties is not true
How many moles of sodium atoms do you have if you have 5.60 ~
1023 atoms of sodium. (The mass of one mole of sodium is 22.99 g.)
Answer:
0.93 mol
Explanation:
Given data:
Number of moles of Na atom = ?
Number of atoms = 5.60× 10²³
Solution:
Avogadro number:
The given problem will solve by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance. The number 6.022 × 10²³ is called Avogadro number.
1 mole = 6.022 × 10²³ atoms
5.60× 10²³ atoms × 1 mol / 6.022 × 10²³ atoms
0.93 mol
A pencil has a density of .875 g/ml it has a mass of 3.5 grams What is the volume
what is not true about group 18
They are gases at room temperature.
They have 8 valence electrons.
They are known as halogens.
They are non-reactive and highly stable.
Answer:
they are known as halogens
Explanation:
everything else is correct
how you will separate pure water from a solution of water and salt
Which of thes statements about heating up land and water is true
Answer:
b its radiant energy that heats up the earth.
Explanation:
Answer:
The answer is D
Explanation:
Heat from the Earth's core and radiation from the Sun is transferred to the surface of the Earth by conduction. The warm land and water radiates infrared, some of which is absorbed by the atmosphere, adding to its thermal energy.
You are asked to write observations about a 100g sample of Nitrogen-16 before it decays , but you running late. In order to make observations, you require at least 5g of material Can make observations you are 57 seconds late to the lab?
Answer:
You can not make the observation in the lab
Explanation:
We must know the amount of Nitrogen-16 that remains after 57 seconds before we can make our conclusion.
Hence, from;
N/No = (1/2)^t/t1/2
Where;
N = amount of Nitrogen-16 present after 57 seconds
No = 100g of Nitrogen-16 originally present
t = 57 seconds
t1/2 = half life of Nitrogen-16 which is 7.13 seconds
Substituting values;
N/100 = (1/2)57/7.13
N/ 100 =(1/2)^8
N/100 = 1/256
256N = 100
N = 100/256
N = 0.39 g
You can not make the observation because you need at least 5g of Nitrogen-16 and only 0.39 g is left after 57 seconds.
The minimum amount of sample required has been 5 grams, while the remaining sample has been 0.39 grams. Thus, it has not been possible to make the observations.
The half life can be defined as the time required for the sample to reduce to half of its initial concentration. The half life can be given as:
Amount remained = Initial amount [tex]\rm \times\;\dfrac{1}{2}^\dfrac{time}{Half-life}[/tex]
The half life of nitrogen 16 has been 7.13 second.
The initial concentration of the sample has been 100 grams.
The concentration of sample remained after 57 seconds has been:
Amount remained = 100 [tex]\rm \times\;\dfrac{1}{2}^\dfrac{57\;sec}{7.13\;sec}[/tex]
Amount remained = 0.39 grams.
The amount of sample remained after 57 seconds has been 0.39 grams.
The amount of sample required for the analysis has been 5 grams, after 57 seconds only 0.39 grams of sample has been remaining. Thus, the student will not be able to made analysis of nitrogen-16.
For more information about the sample decay, refer to the link:
https://brainly.com/question/1831303
A voltaic cell is constructed that is based on the following reaction:
Sn2+(aq)+Pb(s)→Sn(s)+Pb2+(aq).
If the concentration of Sn2+ in the cathode compartment is 1.00 M and the cell generates an emf of 0.16 V , what is the concentration of Pb2+ in the anode compartment?
Answer: The concentration of Pb2+ in the anode compartment is [tex]1.74\times 10^{-6}M[/tex]
Explanation:
[tex]Sn^{2+}(aq)+Pb(s)\rightarrow Sn(s)+Pb^{2+}(aq)[/tex]
Here Pb undergoes oxidation by loss of electrons, thus act as anode. Sn undergoes reduction by gain of electrons and thus act as cathode.
[tex]E^0=E^0_{cathode}- E^0_{anode}[/tex]
Where both [tex]E^0[/tex] are standard reduction potentials.
[tex]E^0_{[Sn^{2+}/Sn]}=-0.14V[/tex]
[tex]E^0_{[Pb^{2+}/Pb]}=-0.13V[/tex]
[tex]E^0=E^0_{[Sn^{2+}/Sn]}- E^0_{[Pb^{2+}/Pb]}[/tex]
[tex]E^0=(-0.14-(-0.13)V=-0.01V[/tex]
Now using Nernst Eqn :
[tex]E=E^0-\frac{0.059}{n}\log\frac{[Pb^{2+}]}{[Sn^{2+}]}[/tex]
[tex]0.16=(-0.01)-\frac{0.059}{2}\log\frac{[Pb^{2+}]}{[1.00]}[/tex]
[tex]0.17=-0.0295\log\frac{[Pb^{2+}]}{[1.00]}[/tex]
[tex]-5.76=\log\frac{[Pb^{2+}]}{[1.00]}[/tex]
[tex]1.74\times 10^{-6}=\frac{[Pb^{2+}]}{[1.00]}[/tex]
[tex][Pb^{2+}]=1.74\times 10^{-6}[/tex]
what term is used to describe the formation of ions in an aqueous solution from a molecular compound
Answer:
Ionization
Explanation:
Molecular compounds are chemical compounds composed of discrete molecules. A molecular compound undergoes ionization when being dissolved in water and the formation of ions are being produced. For example, hydrogen chloride is a molecular compound, when it dissolves in water, ionization is being carried out, and ions are being formed.
[tex]\mathbf{HCl \to H^+_{(aq)} + Cl^-_{(aq)}}[/tex]
In the reaction between Fe and CuCl2, the following statement is true:
This is a single displacement reaction. In this reaction, Iron reacts with aqueous solution of copper chloride, which is blue in colour.
The Iron being more reactive, reduces the copper from its solution to make Iron Chloride, which is green in colour. Fe + CuCl₂ → FeCl₂ + Cu. This is also a redox reaction in which CuCl₂ is a reducing agent and Fe is an oxidising agent.
Thus, the reaction between Iron and Copper sulphate is a redox displacement reaction.
Learn more about Displacement reactions:
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Disclaimer: The question was incomplete. The correct question can be:
In the reaction between Fe and CuCl₂, the following statement is true:
A) It is a single displacement reaction.
B) It is a combination reaction.
C) It is a decomposition reaction.
D) It is a double displacement reaction.
13. what is the precent composition
of Ca (C2 H3 O2) 2
Answer:Ca C2h3o2 2
Explanation
find the molar mass of the compound
ca : 1 X 40.1 = 40.1
c: 4 x 12.01 = 48.04
H: 6 X 1.01 = 6.06
O: 4 X 16 = 64
add these up and get 158.11
then divide 158.11 by each element massand multiply by 100
Ca: 40.01/158.11 X 100 = 25.3%
C: 30.4%
H:3.8%
O: 40.5%
PLEASE HELP
predict the product of the following reactants and the balance.
1. _______CuSO4+ _____NH4OH->
Answer:
CuSO4 + 2NH4OH -----> Cu(OH)2 + (NH4)2SO4
Explanation:
How many elements are in alanine?
Answer:
4 elements carbon hydrogen nitrogen and oxygen are present in alanine.
Explanation:
Its formula is C3H7NO2 which show all above 4 elements
How many moles of C are in a diamond that has a mass of 0.80 g? (Atomic mass of C=12.01g)
Answer:
0.066 moles
Explanation:
0.80/12.01=0.0666
Wax melts when it is heated. Which most likely describes what is true of the result of this reaction?
melting of wax is a physical reaction, because the same amount of wax exists before and after the change.
physical reaction is a change from one state (solid or liquid or gas) to another without a changing in the chemical composition.It alters the form, shape or appearance of a material but does not convert the material into a new substance. examples Freezing Water, Sanding a piece of paper, Bending a paper clip, Mixing oil and vinegar etc both physical and chemical changes obey the law of conservation . It also entails that the mass of a substance present before a reaction should be equal to the mass obtained after the reaction.To know more about physical reaction visit :
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Which of the following is an ion with a negative one charge?
OH₂C-Ö:
O:0-N=0:
: 0 N
30:
All of these choices.
O None of these choices.
Answer:
[no2]- it have 1 negative charge
O-N=O
this Single bond O having negative charge because oxygen need 2 electrons to complete its octet and it have only one bond to complete its octet it having one more electron and this one one more electron creates 1 negative charge on this compound
the most well-known biogenic d-elements
Answer:
Zn, Cu, Fe, Mn, Co, Mo
Explanation:
Biogenic elements are chemical elements constantly present in organisms and having definite biological significance(Bowen, 1966).
There are many of these biogenic elements in nature. Among the elements of the d-block, Zn, Cu, Fe, Mn, Co, Mo are worthy of mention among others.
Free ions of d- block metals are not found in the body. The elements are present in the form of bioinorganic complexes of the respective metals. They commonly exist as co-factors of proteins that carry out essential biological functions.
Type of bond where two elements form oppositely charge ions that are attracted
Answer:
If electronegativity difference is greater than 1.7 then ionic bond other wise covalent bond
Explanation: