Answer:
Valence electrons are the outermost of electrons.
Explanation:
valence electrons are the outermost electrons of an atom located in the shell/ orbit
How many moles is 78.0 grams of sodium?
Answer:3.39
Explanation:
How many deciseconds are
in 554 seconds?
Give your answer in standard form.
Answer:
5540
Explanation:
Answer:
5,440
Explanation:
10 deciseconds = 1 seconds
554 seconds = 5,440 seconds
A chemistry teacher adds red food coloring to water and students observed the dye spreading out to fill the container. Is the teacher
demonstrating a physical or chemical change?
Answer:
its obviously a chemical change
Explanation: Facts
The addition of the food color in water only causes the change in the cor of water but no new substance is formed. Therefore, the teacher is restarting the physical change.
What is a physical change?A physical change can occur when the characteristics of the matter change but the identity does not. Physical changes are classified as: reversible and irreversible. For example, the melting of water is reversible in nature since the melted ice cube will be refrozen.
Physical change can be described as a kind of change where only physical properties of matter such as odor, color, solubility, etc. can change. During physical changes, there is no chemical bonds are broken or formed between atoms of the substance.
The chemical composition as well as the chemical nature of the substance remains unchanged during a physical change. The molecules of matter can rearrange without changing the internal composition of matter.
Therefore, adding food color to water is a physical change as no new substance formed.
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What number should be placed in front of Fe to balance this chemical
equation?
_Fe+302>2Fe2O3
A. 8
B. 2
C. 1
D. 4
the answer is B. 2
because there is 2 iron on the right side so you need another two on the left side to balance it out
Explain why copper has a high thermal conductivity.
Explain why copper has a high electrical conductivity.
i just need like a basic explanation for an essay
Explanation:
So copper is a lattice of positive copper ions with free electrons moving between them.
what is atomic mass in Chemistry
Answer:
the average mass of the atoms of an element measured in atomic mass unit (amu, also known as daltons, D)
Explanation:
Help please, take a screenshot who will answer will be brainiest.
Answer:
1. Metals are typically shiny, and good at conducting electricity and heat and have a high melting point. Non-metals are typically dull, and poor at conducting electricity and heat and have a low melting point.
2. Element C and element E.
3. a. It is a poor conductor of electricity
b. It is a good conductor of heat
Explanation:
As it says in the chart at the top of the picture, metals are typically good at conducting electricity and heat and have a high melting point. Non-metals are typically poor at conducting electricity and heat and have a low melting point.
DO the postulates of daltons atomic theory explain the law of consrevetion of mass and thelaw of constant composition
Answer:
see answer
Explanation:
DO the postulates of Daltons atomic theory explain the law of conservation of mass and the law of constant composition.
Dalton's Atomic Theory Postulates1. Everything is composed of atoms, which are the indivisible building blocks of matter and cannot be destroyed or divided any further.
2. All atoms of a single pure element are the same in size and mass
3. Atoms of different elements vary from each other in size and mass.
4. Compounds are produced through different simple whole-number combinations of atoms to produce molecules.
5. Anywhere a compound exists, it will have the same atoms in the same ratio.
6. A chemical reaction between compounds is a re-arrangement of atoms
The law of conservation of mass is shown in 2, 4. and 5.
The law of constant co,position is shown in 2, 4, 5, and 6
Complete the sentence.
Atoms form chemical bonds to satisfy the ______
rule and to become _______
Assume that the test tube shown started out having 10.00 g of mercury(II) oxide. After heating the test tube briefly, you find 1.35 g mercury(II) oxide left and 8.00 g of liquid mercury. How much oxygen gas was produced by the chemical reaction? Show your work.
This problem is providing information about the initial mass of mercury (II) oxide (10.00 g) which is able to produce liquid mercury (8.00 g) and gaseous oxygen and asks for the resulting mass of the latter, which turns out to be 0.65 g after doing the corresponding calculations.
Initially, it is given a mass of 10.00 g of the oxide and 1.35 g are left which means that the following mass is consumed:
[tex]m_{HgO}^{consumed}=10.00g-1.35 g=8.65 g[/tex]
Now, since 8.00 grams of liquid mercury are collected, it is possible to calculate the grams of oxygen that were produced, by considering the law of conservation of mass, which states that the mass of the products equal that of the reactants as it is nor destroyed nor created. In such a way, the mass of oxygen turns out to be:
[tex]m_{O_2}=8.65g-8.00g=0.65g[/tex]
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https://brainly.com/question/14502981https://brainly.com/question/14236219All the members of this family (inner transition metals) are both ______________ and _____________.
(HURRY PLS)
Answer:
The actinides and the lanthanides
The energy released by a nuclear fusion reaction is produced when
1. energy is converted to mass
2. mass is converted to energy
3. heat is converted to temperature
4. temperature is converted to heat
Answer:
2
Explanation:
energy produced in nuclear fusion or even fission is due to mass defect and it can be calculated by Einstein equation e=mc2
The statement, that describes energy released by a nuclear fusion reaction is produced is "mass is converted to energy."
What is nuclear fusion?Nuclear fusion is the process by which two light atomic nuclei merge to produce a single heavier one, releasing huge quantities of energy in the process.
A fusion reaction occurs when two light nuclei combine to form a single heavy nucleus. Because the overall mass of the resulting single nucleus is smaller than the mass of the two initial nuclei, the process releases energy.
That is, nuclear energy refers to the energy released as a result of mass loss during the nuclear fusion processes. Both of these processes transform mass loss into energy in accordance with Einstein's mass-energy ratio, E = [tex]mc^{2}[/tex]. As a result of the fusion reaction, mass is destroyed and energy is released.
Hence, the correct answer is 2.
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PLZ HELP
What are 3 genetic disorders caused by either missing or extra chromosomes? Provide a brief short explanation of what causes the disorder and some potential symptoms.
Answer:
Single-gene disorders, where a mutation affects one gene. Sickle cell anemia is an example.
Chromosomal disorders, where chromosomes (or parts of chromosomes) are missing or changed.
Complex disorders, where there are mutations in two or more genius.
Hope it help^^
Brainliest me pls
Which is the formula for nitrogen trihydride? NH3 N3H 3NH N3H3
the answer isssssssssssssssssssssss... Nh3.
Answer: A.) NH3
Explanation:
1. Why fractional distillation has
fractionating column but not in simple
distillation?
Answer:
fractional distillation leads to better separation
Calculate the molecular mass of the element
They give:H=1,AI=27,S=32,0=16,Cu=64,P=31,Mg=24,N=14,Na=23
Answer:
Na2SO4
2×23 + 32 + 4×16
46 + 32 +64
=142g
Why do metals form cations and nonmetals form anions?
[tex]▪▪▪▪▪▪▪▪▪▪▪▪▪ {\huge\mathfrak{Answer}}▪▪▪▪▪▪▪▪▪▪▪▪▪▪[/tex]
Metals have tendency to loose electrons in order to get noble gas configuration, therefore they loose electrons to form Cations (positively charged ions)
for example ~ Sodium forms Na+
And
Non - metals have tendency to gain electrons in order to attain noble gas configuration , hence they gain electron from somewhere and bears a negative charge forming Anion.
for example ~ Chlorine forms Cl-
In a crystal of an ionic compound, each cation is surrounded by a number of what?
Answer:In a metal, atoms readily lose electrons to form positive ions (cations). These ions are surrounded by delocalized electrons, which are responsible for conductivity.
Explanation:
Due to the structure of ionic compounds, in a crystal of an ionic compound, each cation is surrounded by a number of oppositely-charged anions.
What are ionic compounds?Ionic compounds are compounds that are composed of oppositely charged ions held together by strong electrostatic forces of attraction.
The ions present in an ionic compound are the positively-charged ions known as cations and the negatively-charged ions known as anions.
Each of the oppositely-charged ions are attracted to each other.
Therefore, in a crystal of an ionic compound, each cation is surrounded by a number of oppositely-charged anions.
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33. Which element in Period 5 of the Periodic Table
is a transition element?
A) Sr
B) Ag C) Sb
D) Xe
Silver or Ag is the transition element present in period 5 of the periodic table.
What is periodic table?
Periodic table is a tabular arrangement of elements in the form of a table. In the periodic table, elements are arranged according to the modern periodic law which states that the properties of elements are a periodic function of their atomic numbers.
It is called as periodic because properties repeat after regular intervals of atomic numbers . It is a tabular arrangement consisting of seven horizontal rows called periods and eighteen vertical columns called groups.
Elements present in the same group have same number of valence electrons and hence have similar properties while elements present in the same period show gradual variation in properties due to addition of one electron for each successive element in a period.
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If the absorbance of the mixture is 0.20 at 453 nm, how many moles of Fe3 (aq) were present in the 100. mL sample
Despite this problem misses out crucial information for its solution, it turned out possible to come up with the attached absorbance graph, which shows the behavior of the absorbance of the sample with respect to the concentration at 453 nm.
As you can see, there is a red line and circle pointing out the concentration at which the sample has an absorbance of 0.20 (y-axis) which turns out to be 4x10⁻⁵ M (x-axis).
Now, since we require the moles of the iron (III) ions present in 100. mL of the sample, we recall the concept of molarity, which requires moles and volume in liters:
[tex]M=\frac{n}{V}[/tex]
Thus, since all the Fe⁺² in FeSCN⁺² is converted to Fe⁺³ we can find out the moles as shown below:
[tex]n=4x10^{-5}\frac{mol}{L} *0.100L\\\\n=4x10^{-6}mol[/tex]
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https://brainly.com/question/5650600https://brainly.com/question/13490034An 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 :(
Which two factors will improve the efficiency of an inclined plane?
the answer is using rollers in conjunction with inclined plane.
Why can Marco hear the music, even though he is not in the same room as the speaker?
Answer:
Sound Travels
Explanation:
Sound waves can travel, and that makes it so that even though Marco is in a different room, he can hear the music. Depending how loud the music is and how thick the walls car, the sound can travel through the walls.
What is the maximum number of electrons in the following energy level? n = 1
Maximum number of electrons in nth energy level
[tex]\\ \sf\longmapsto 2n^2[/tex]
Now
n=1Max electrons
[tex]\\ \sf\longmapsto 2(1)^2[/tex]
[tex]\\ \sf\longmapsto 2e^-[/tex]
an empty aerosol can at 25°c still contains gas at 1.00 atmosphere pressure. if an empty can is thrown into a 475°c fire, what is the final pressure in the heated can?
The final pressure in the heated can is 2.51 atm
From the question given above, the following data were obtained:
Initial temperature (T₁) = 25 °C = 25 + 273 = 298 K
Initial pressure (P₁) = 1 atm
Final temperature (T₂) = 475 °C = 475 + 273 = 748 K
Final pressure (P₂) =?The final pressure can be obtained as illustrated below:
[tex] \frac{P_1}{T_1} = \frac{P_2}{T_2} \\ \\ \frac{1}{298} = \frac{P_2}{748} \\ \\ cross \: multiply \\ \\ 298 \times P_2 = 1 \times 748 \\ \\ divide \: both \: side \: by \: 298 \\ \\ P_2 = \frac{748}{298} \\ \\ P_2 = 2.51 \: atm[/tex]
Therefore, the final pressure in the heated can is 2.51 atm
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michela and simone are camping in a ent during some hot weather
what type of rock forms when heat or pressure change an existing rock?
Answer:
Metamorphic rocks started out as some other type of rock, but have been substantially changed from their original igneous, sedimentary, or earlier metamorphic form. Metamorphic rocks form when rocks are subjected to high heat, high pressure, hot mineral-rich fluids or, more commonly, some combination of these factors.
Explanation:
Dividing the distance a wave travels by the time it takes to travel that distance gives you the wave’s speed.
True
False
Answer:
true
Explanation:
hope this helps
Which electrophiles can react with an enol?
THE MOLECULE HAS A C=C AND AN -OH GROUP, SO IT IS CALLED AN ENE/OL, I.E., AN ENOL. ENOLS CAN BE FORMED ONLY FROM CARBONYL COMPOUNDS WHICH HAVE ALPHA HYDROGENS. THEY CAN BE FORMED BY ACID OR BASE CATALYSIS, AND ONCE FORMED ARE HIGHLY REACTIVE TOWARD ELECTROPHILES, LIKE BROMINE.
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.