Answer:
its D. answers many questions about atoms.
The modern-day quantum model of the atom is better than John Dalton’s model because it " answers many questions about atoms."
What is quantum model ?This concept also referred to as the quantum mechanical and wave mechanical model, would be the cornerstone of contemporary atomic theory. The fact that an electron inside an atom may only exist in a limited range of states or energy is analogous to a standing wave.
What is John Dalton’s model ?Dalton proposed that the concept of atoms will be used to explain the laws of conservation of mass as well as definite proportions. Imagining atoms as "solid, massy, hard, impenetrable, moving objects," he claimed that almost all matter would be composed of these tiny, indivisible particles.
Dalton also stated that almost no atom might be formed, converted into another, as well as destroyed. The complex shapes of orbitals also known as electron clouds used in the quantum mechanical atomic model are areas of space where an electron is likely to be present. So rather than being based on certainty, this model would be probability based.
Therefore, the correct answer will be option (D)
To know more about John Dalton’s model and quantum mechanical atomic model
https://brainly.com/question/12708372
#SPJ3
4. Pb + FeSO4 → PbSO4 + Fe
what type of reaction?
Oxidation- Reduction reaction
The MSDS for propane gives it a health rating of 1, a flammability rating of 4, and a reactivity rating of 0. According to the MSDS, which best describes propane? highly corrosive highly toxic highly flammable highly reactive.
Propane has MSDS rating for flammability 4, thus the compound has been highly flammable. Thus, option C is correct.
The MSDS has been the Material Safety Data Sheet . It has been given for the compounds hazardous levels. The compounds have been checked on various parameters and ranked on the scale of 0 to 4.
The compounds being less value in the parameter has 0 value, while 4 has been the maximum value.
The MSDS rating for propane has been able to deliver the compound to be:
Health rating: 1The compound has been less positive towards the health.
Flammability: 4The compound has been highly flammable.
Reactivity: 0The compound has been least reactive.
Since, propane has MSDS rating 4 for flammability, the compound has been highly flammable. Thus, option C is correct.
For more information about the MSDS rating, refer to the link:
https://brainly.com/question/2852656
Answer:A) Highly corrosive but not highly flammable
Explanation:
right on edge :)
How do you prepare 500ml of 1.77M H2SO4 solution from an 18.0M H2SO4 Stock solution
Answer:
Take 49.2-ml of 18.0 M H2SO4 stock solution and pour it into a 500-ml volumetric flask. Fill to the 500-ml line with distilled water to make 1.77M H2SO4 solution.
Explanation:
use the formula M1V1=M2V2
volume must be in liters(L)
[tex](1.77)(500 \times {10}^{ - 3} ) = (18)v2 \\ 0.885 = 18v2 \\ v2 = \frac{0.885}{18} \\ v2 = 0.04916[/tex]
0.04916L × 1000 = 49.16 ml = 49.2 ml
One of the main properties used to describe a population
Answer:
Birth rate, death rate, emigration, immigration, or a census.
Explanation:
1. Explain the difference between genetic, environmental, social, and pathogenic factors.
2. How do pathogens spread?
3. How can we, as humans, prevent transmission of pathogens?
4. List three ways the environment can affect personal health.
1. Genetic factors are those where the genetic condition of an individual is capable of increasing the probability of developing certain diseases.
Environmental factors include the diversity of environmental stresses such as population density, temperature, food and pollutants that impact human health.
Social factors are related to the interaction of groups through culture, social class and family structure, which also have an effect on population health.
Pathogenic factors, on the other hand, are those transmitted by agents such as viruses, fungi, bacteria and protozoa, which colonize a host by adhering to cells and evading immunity, generating diseases.
2. The transmission of pathogens can occur in several ways, such as contact with bodily fluids from infected people, cross-transmission or through being spread through particles in the air.
3. We can prevent the transmission of pathogens through proper hygiene habits, healthy eating, vaccination against infectious diseases and avoid contact with other people if you have a communicable disease.
4. The environment can affect personal health through climate change, pollution and lack of infrastructure that lead to less access to quality food and basic health conditions.
Learn more here:
https://brainly.com/question/13179079
Two protons and two neutrons are released as a result of this reaction. Superscript 222 subscript 86. Rn Right arrow superscript 218 subscript 84. Po ? Which particle is released? one alpha particle two beta particles one alpha and one beta particle one high-energy photon.
The particle released in the reaction has been an alpha particle. Thus, option A is correct.
The release of protons and neutrons in a reaction has been nuclear reactions. The reactions results in the change in the atomic mass of the atom, with the formation of new atom. The extra mass has been released in the form of energy.
The release from the given reaction has been:
[tex]\rm ^{222}_{66}Rn\;\rightarrow\;^{218}_{84}Po\;+\;^A_ZX[/tex]
Where, X has been the particles that has been released with the nuclear reaction. The superscript A has been the Mass of particle, and subscript Z has been the atomic number.
According to the law of conservation, the mass has been constant on both the product and the reactant side. Thus, the mass and atomic number of eliminated particles has been given as:
[tex]\rm 222=218+A\\A=222-218\\A=4[/tex]
The atomic mass of the particle has been 4.
[tex]\rm 86=84+Z\\Z=86-84\\Z=2[/tex]
The atomic number of the particle has been 2.
The element with atomic mass 4, and atomic number 2 has been the Helium particles, [tex]\rm ^4_2He[/tex]. It has been an alpha particle. Thus, the particle released in the reaction has been an alpha particle. Thus, option A is correct.
For more information about the particles released, refer to the link:
https://brainly.com/question/2600896
Answer:
A
Explanation:
how many neutrons of atomic mass is 31 and atomic number is 12
[tex]▪▪▪▪▪▪▪▪▪▪▪▪▪ {\huge\mathfrak{Answer}}▪▪▪▪▪▪▪▪▪▪▪▪▪▪[/tex]
As we know, Number of protons = Atomic Number
So,
Number of protons = 12And, Atomic mass = Number of protons + Number of Neutrons (N)
therefore ~
31 = 12 + N N = 31 - 12 N = 19Number of Neutrons = 19
Desperate Please Hurry
What was the evidence that Earth was round before there were photos from space?
Answer:
Explanation:
Are there any awnser choices?
How to get rid of high cholesterol?!
Please tell me
you have to drink a lot of water and 67890
Ores contain enough metal to make extraction of the metal ______
economical.
reversible.
carbon neutral.
Answer:
oxide
Explanation:
True/False: For the same system, heterogeneous nucleation will occur at less undercooling than homogeneous nucleation.
Answer:
True.Explanation:
same system, heterogeneous nucleation will occur at less undercooling than homogeneous nucleation.
helllloooook this makes no sense help me plz
may i ask?
How do you use this app?
A sample of gas occupies 20 mL at -109 degree C. What volume does the sample
occupy at 65 °C?
Answer: V2= 41.2mL
Explanation:
Givens:
* V1= 20ml
* T1 = -109 ⁰C --> K= ⁰C + 273.15 --> 164.15 K
* V2 = ??
* T2= 338.15 K
Use Charles law V1/T1 = V2/T2
Since we are looking for V2 we can rearrange the formula to
V2= (T2 x V1) /T1
V2= (338.15K x 20mL) / 164.15 K
V2= 41.2mL
NOTE:
Temperature should always be in K not in ⁰C or ⁰F
To convert from C to K use
*K= ⁰C + 273.15
Enter your C value in the ( ⁰C ) and you can get K
Answers..,.ًًًًًًًًًًًًًًًًًًًًًًًًًًًًً………..,.,.,…,.,.,.,
Answer:
1) actual yield - 2.675 g
Theoretical yield - 4.0539 g
2)a) 41.257 g
b) 0.6857moles
c) 23 g
Explanation:
1)
Theoretical yield is the mass of the product that can obtain from the equation, it is not practical.
Theoretical yield:
Mr of SiO2 - 60
Moles of SiO2 - 2.339/60 = 0.03898 moles
Mr of SiF4 - 104
Mass of SiF4 - 0.03898 * 104 = 4.05392 g
2)
a)
mr of B2H6 - 28
Moles of B2H6 - 36.1/28 = 1.2893 moles
Mr of O2 - 32
Mass of O2 - 32 * 1.2893 = 41.257 g
b)
Moles of B2H6 - 19.2/28 = 0.6857 moles
Stoichiometry 1:1 ratio between B2H6 and H2O
So moles of H2O is 0.6857
c) moles of O2 - 2/24(r.t.p) = 0.083 moles
Mass of B2H6 - 0.083 * 28 = 2.3 g
Help me please…………..d
what is the difference between nitrite and nitrate
Answer:
Nitrite:
Formula : NO₂⁻1 nitrogen molecule and two oxygen molecules with an excess electron.Angular shapeNitrate:
Formula: NO₃⁻1 nitrogen molecule and three oxygen molecules with an excess electron.Trigonal planar structure.[tex]\rule[225]{225}{2}[/tex]
Hope this helped!
~AH18071. what property of gas does not change?
2. Name two gases besides oxygen found in Earth's atmosphere
Answer:
hydrogen and nitrogen or something?
Explanation:
Answer:
nitrogin and i forgot the other one srry!!
Explanation:
What do these red/yellow/orange-precipitate reactions have in common? (choose
the best answer)
They all made the same color.
They all have a barium (Ba+2) cation.
They all have a chromate (CrO4-2) ion.
They all have a chloride ( C1-1) ion.
Answer:
3 is the correct I think so
Answer:
They all have a chromate (CrO4-2) ion.
Explanation:
Crumpling and tearing cause physical changes to a piece of paper.
Which two characteristics of the paper change?
A. Size
B. Reactivity
I C. Identity
I D. Shape
Please help I’ll give brainlist and no spamming or links just please help
size and shape. only the appearance of the paper will have changed, but is reversible.
Pls some one help
1 mark question
Answer:
See below
Explanation:
Helium belongs to group VIII of the periodic table "Noble gases". It has only 1 electronic shell and that too contains 2 electrons according to the accommodation of the shell. Hence, it's electronic shell is complete. This is the reason, Helium is chemically unreactive.
[tex]\rule[225]{225}{2}[/tex]
Hope this helped!
~AH1807Which animal is found in the desert?
monkeys
parrots
buffalo
meerkats
Answer:
meerkats
Explanation:
what are isotopes and explain why
A student is asked to describe three random
elements found on the periodic table. All three
elements will FOR SURE have which of the two
following characteristics?
A. similar color and texture
B. shininess and value
C. mass and volume
D. similar boiling and freezing points
All three elements in the periodic table will for sure have characteristic of mass and volume.
What is an element?
An element is defined as a substance which cannot be broken down further into any other substance. Each element is made up of its own type of atom which is characteristic of it's own. Due to this reason all elements are different from one another.
Elements can be classified as metals and non-metals. Metals are shiny and conduct electricity and are all solids at room temperature except mercury. Non-metals do not conduct electricity and are mostly gases at room temperature except carbon and sulfur.
The number of protons in the nucleus is the defining property of an element and is related to the atomic number.All atoms with same atomic number are atoms of same element.
Learn more about element,here:
https://brainly.com/question/14347616
#SPJ2
How many molecules are in 10 grams of sulfur hexafluoride (SF6)? Molar Mass: 146.06 g/mol
Answer: 4.123 x 10^22
Explanation:
The first step is to determine how many moles of sulfur hexafluoride (SF6) there are. To do this, you must take the mass of the SF6 (10g) and divide it by the molar mass (146.06).
[tex]10g * \frac{1 mol}{146.06 g}= 0.068465 mol[/tex]
Then you must use Avagadros number to find the number of molecules.
Avagadros number is the number of molecules in 1 mol of a substance, so a simple multiplication will do the trick.
[tex]0.068465mol * \frac{6.022 * 10^{23}}{1mol} = 4.123*10^{22}[/tex]
And that is your answer. There are 4.123 x 10^22 molecules of sulfur hexafluoride in 10g of it.
Which of the following is true for a nuclear reaction?
O Electrons are lost
Electrons are gained
O Identity of element changes
Oldentity of element remains same
True statement for a nuclear reactions is that it changes the identity of the element.
What are nuclear reactions?Nuclear reactions are those reactions in which changes in the nucleus of atoms take place in the form of fission and fussion.
As it is said that changes are taking place in nucleus so the electrons are not gained or lost in this reactions.Identity of the element changes as atomic number of element changes due to change in the number of protons.Hence identity of element changes.
To know more about nuclear reactions, visit the below link:
https://brainly.com/question/984564
How do characteristic properties help you determine whether a chemical
change or a physical change has occurred? I
Answer: The difference between a physical reaction and a chemical reaction is composition. In a chemical reaction, there is a change in the composition of the substances in question; in a physical change there is a difference in the appearance, smell, or simple display of a sample of matter without a change in composition.
Explanation:
A horticulturalist wants to produce geraniums with specific characteristics.
She knows that the trait of red flowers is governed by the allele R (RR and Rr) and the trait of white flowers is governed by the allele r(rr).
The horticulturalist crosses two geraniums from the F1 generation.
Look at the Punnett square to see this cross.
R r
R RR Rr
r Rr rr
Which ratio of red-to-white flowering plants would she expect to see in the phenotypes of the F2 generation?
all red
3 red : 1 white
1 red : 3 white
2 red : 2 white
Yo,
In Geranium plant life red vegetation is given by using the allele R this is dominant (so RR or Rr ) genotype will produce crimson plant life.
If we communicate approximately the connected punnet square which i took from the workout e book, you could see that there was a cross made among vegetation with heterozygous genotype for red flora.
P1: Rr X Rr
Gametes: R: r : R : r
F1: RR: Rr: Rr: rr
so there is three: 1 in F1 offspring for red to white plant life.
Now the query is set f2 technology, while we cross F1 generation suppose we do a move of Rr and rr from F1 generations allow us to see what takes place.
F1: Rr: rr
Gametes: R: r: r: R
F2 : Rr : rr: Rr: rr
Rr: purple flowers
rr: White flora:
So the ratio in F2 era might be 2 crimson : 2 white. Please see connected punnet squares (first one for query) and the second of F1 move for better know-how.
I'm hoping that this will benefit you, so from my assumption and study it'd be 2 crimson : 2 white, if this is indeed the one i'm thinking of since nothing else was provided, if not please correct me.
Answer: 2 red : 2 white
Explanation:
I know
Can someone help me with this please
That is an ionic bond.
Explanation:
It has cations and anions
Explain how wind and water can create a sand dune along an ocean beach
Answer: A dune is a mound of sand formed by the wind, usually along the beach or in a desert. Dunes can also be formed by strong currents beneath the water.
What is the formula for atomic weight amu of neon
Answer:
abundance of the first isotope times the Mass of the first isotope