40567⁰ kkkkkkkkkkkkkkkkkkkkkkmeow
Explanation:
cuz I got a 100
In a molecule of calcium sulfide, calcium has two valence electron bonds, and a sulfur atom has six valence electrons. How many lone pairs of electrons are present in the Lewis structure of calcium sulfide?
A. one
B. two
C. three
D. four
E. none
Also, state why.
Answer:
E
because it forms the ionic bond but not covalent.
you have a friend who is using a recipe for flat from american cookbook you notice that he set your over temperature at 175F° what you advise him to do?
Answer:
I will give them advice, that do the power of flame low....
Explanation:
thanks.
fill in the blank please
amino acids as _____ are to words
Answer:
Sentences are where there is a beginning and an end of a section of a paragraph. Letters are individual parts of sentences.
The answer that would make the MOST sense would be SENTENCES
How many moles are in 3.4 x 10-7 grams of Silicon dioxide, SiO2?
Answer:
Number of moles = 0.057 × 10⁻⁷ mol
Explanation:
Given data:
Mass of SiO₂ = 3.4 × 10⁻⁷ g
Number of moles = ?
Solution:
Number of moles = mass/molar mass
Molar mass of SiO₂ = 60 g/mol
by putting values,
Number of moles = 3.4 × 10⁻⁷ g / 60 g/mol
Number of moles = 0.057 × 10⁻⁷ mol
What else is produced when sodium carbonate decomposes?
Na2Co3 - Na2O+
Answer:When a single compound breaks down into two or more compounds or elements in a chemical reaction then it is known as decomposition reaction.
The chemical symbol for sodium carbonate is .
The decomposition of sodium carbonate is:
The decomposition of sodium bicarbonate, will result in the formation of sodium oxide, and carbon dioxide, .
Hence, carbon dioxide, will produce with sodium oxide, on decomposition of .
Explanation:Na2CO3 Na2O +CO2 CO2 is the answer
please help me i will give brain list
Answer:
a. pentane = C5H12
b. Heptane = C7H16
c. Hexyne = C6H10
d. Octene = C8H16
e. Nonane = C9H20
Hope it helps.
1-pentene
Molecular Formula C5H10
Condensed Structural FormulaCH2=CH(CH2)2CH3
Melting Point (°C)–138
Boiling Point (°C)30
2- heptane is the straight-chain alkane with the chemical formula H3C(CH2)5CH3 or C7H16, and is one of the main components of gasoline (petrol).
When the volume of a gas is
changed from 3.6 L to 15.5 L, the
temperature will change from
°C to 87°C.
Assume that the number of moles and the
pressure remain constant.
Be sure to notice that temperatures are
given in °C!
Answer:
-189.55°C
Explanation:
Given data:
Initial volume of gas = 3.6 L
Final volume of gas = 15.5 L
Initial temperature = ?
Final temperature = 87°C (87+273 = 360 K)
Solution:
The given problem will be solve through the Charles Law.
According to this law, The volume of given amount of a gas is directly proportional to its temperature at constant number of moles and pressure.
Mathematical expression:
V₁/T₁ = V₂/T₂
V₁ = Initial volume
T₁ = Initial temperature
V₂ = Final volume
T₂ = Final temperature
Now we will put the values in formula.
V₁/T₁ = V₂/T₂
T₁ = V₁T₂ /V₂
T₁ = 3.6 L × 360 K / 15.5 L
T₁ = 1296 L.K / 15.5 L
T₁ = 83.6 K
Kelvin to °C:
83.6 K - 273.15 = -189.55°C
4.which is a product of the process shown above?
a. carbon dioxide
b. sugar
c. sunlight
d. water
5.where does the energy that drives this process come from?
a. oxygen
b. sugar
c. sunlight
d. water
Answer:
4. b 5.C
Explanation:
Photosynthesis makes sugar for plants and sunlight is the energy used to convert CO2 and water into glucose
The product of the process of photosynthesis is sugar and the energy to dive the process of photosynthesis comes from sunlight.
What is photosynthesis?Photosynthesis is defined as a process by which plants and other photosynthetic organisms convert the light energy in to chemical energy through the process of cellular respiration.
Some of the energy which is converted is stored in molecules of carbohydrates like sugar and starches which are made up of from carbon dioxide and water . Photosynthetic organisms which can perform photosynthesis are algae and cyanobacteria. Photosynthesis is largely responsible for producing and maintaining the content of oxygen in earth's atmosphere.
The process begins with proteins absorbing light energy which are called reaction centers and contain a green pigment which is called chlorophyll . In plants ,these pigments are present inside organelles called chloroplasts while in bacteria they are present in plasma membrane.
Learn more about photosynthesis,here:
https://brainly.com/question/26494694
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If 33.9g NaCl are mixed into water and the total mass is 578g, what is the CHANGE in freezing if Kb= - 1.82C/M (molal)? Assume NaCl does not dissociate in solution.
Answer:
-1.82 °C
Explanation:
Step 1: Given data
Mass of NaCl (solute): 33.9 gMass of water (solvent): 578 g = 0.578 kgFreezing point depression constant for water (Kb): -1.82 °C/mStep 2: Calculate the molality of the solution
We will use the following expression.
m = mass of solute / molar mass of solute × kg of solvent
m = 33.9 g / 58.44 g/mol × 0.578 kg
m = 1.00 m
Step 3: Calculate the freezing point depression (ΔT)
The freezing point depression is a colligative property that, for a non-dissociated solute, can be calculated using the following expression:
ΔT = Kb × m
ΔT = -1.82 °C/m × 1.00 m
ΔT = -1.82 °C
What would have a higher boiling point water or hydrocarbon ( from penny liquid stacking)
Answer:
Im pretty sure its hydrocarbon
Explanation:
Show the calculation of the molality of a solution made by dissolving 15.9 grams of Ca3(PO4)2 in 400 grams of water.
The molality of a solution : 0.128 m
Further explanationGiven
15.9 g of Ca3(PO4)2 in 400 grams of water.
Required
The molality
Solution
molality = mol solute / kg solvent
solute= Ca3(PO4)2(MW=Molecular Weight: 310.2 g/mol)
mol solute :
[tex]\tt \dfrac{15.9}{310.2}=0.0512[/tex]
The molality :
[tex]\tt \dfrac{0.0512}{0.4~kg}=0.128~m[/tex]
Elisa feels tired because she has a condition that affects whether the right molecules are getting to her cells. If her body were functioning correctly, this is what would happen with oxygen:
Answer:
It would be working properly and providing her energy for her daily activities.
Explanation:
Hello!
In this case, since her oxygen is actually working properly, it is going to be travelling throughout her entire body (via blood) and therefore carbon dioxide would be released as the exhalation product due to cellular respiration carried out in the alveoli which provides energy for her daily activities.
However, the intrusion of different molecules to oxygen into her cells may affect the rate at which cellular respiration is carried out and therefore she may feel tired because such process provides energy to the body.
Best regards!
what's the formula for na and f , ca and br , mg and O
Answer:
NaF, CaBr2, MgO
Explanation:
Hi! For this problem, you are going to want to look at the charges of the elements in order to write their formulas.
NaF: Na has a charge of +1 and F has a charge of -1. This means that they have a 1:1 ratio and the formula is written as such - NaF.
CaBr2: Ca has a charge of +2 and Br has a charge of -1. For this problem you want to make sure that their formal charge (the charge of the entire molecule) equals 0. This means that the negative charges need to equal the positive charges. Looking at this, you are going to need to Br ions with a charge of -1 to equal one Ca ion with a charge of +2 - CaBr2.
MgO: Mg has a charge of +2 and O has a charge of -2. This means that they have a 2:2 ratio which simplifies to a 1:1 ratio and the formula is written as such - MgO.
Hope this helps!
What ratio of concentration of ammonia and ammonium chloride should be mixed to
prepare a buffer solution of pOH 5? (Kb for NH3 =1.8 x 10-4)
The ratio of concentration of ammonia and ammonium chloride : 0.05
Further explanationGiven
pOH=5
Kb for NH3 =1.8 x 10-4
Required
The ratio of concentration of ammonia (NH₃) and ammonium chloride(NH₄Cl)
Solution
Solutions containing ammonia and its salt: ammonium chloride are called alkaline buffers
Can be formulated : ( for the same of the volume, mol=concentration)
[tex]\tt \displaystyle [OH-]=Kb\times\frac{weak\:base\:mole}{salt\:mole\times valence}[/tex]
pOH=-log [OH⁻]
pOH=5⇒[OH⁻]=10⁻⁵
Valence for NH₄Cl = 1, so the concentration ratio :
[tex]\tt 10^{-5}=1.8\times 10^{-4}\times \dfrac{[~NH_3]}{[NH_4Cl]}\\\\0.05=\dfrac{[~NH_3]}{[NH_4Cl]}[/tex]
How is the kinetic energy of the particles of a substance affected during a phase change?
A.) Kinetic energy increases during exothermic changes and decreases during endothermic changes.
B.) Kinetic energy decreases during exothermic changes and increases during endothermic changes.
C.) Kinetic energy does not change, but the potential energy does.
D.) Kinetic energy changes in the opposite way that the potential energy changes.
Answer: A. Kinetic energy increases during exothermic changes and decreases during endothermic changes
Explanation: During an exothermic change potential energy is converted to kinetic energy. I hope this is correct. :)
Answer:
C
Explanation:
In the acetylene torch, acetylene gas (C2H2)(C2H2) burns in oxygen to produce carbon dioxide, water, and energy: 2C2H2(g)+5O2(g)⟶Δ4CO2(g)+2H2O(g)2C2H2(g)+5O2(g)⟶Δ4CO2(g)+2H2O(g) You may want to reference (Pages 241 - 243) Section 7.7 while completing this problem. Part A How many moles of O2O2 are needed to react with 1.85 molmol of C2H2C2H2? Express your answer to three significant figures and include the appropriate units. nn(O2O2) = nothingnothing SubmitRequest Answer
Answer:
4.63 mol
Explanation:
Step 1: Write the balanced complete combustion reaction of acetylene
2 C₂H₂(g) + 5 O₂(g) ⟶ 4 CO₂(g) + 2 H₂O(g)
Step 2: Establish the appropriate molar ratio
According to the balanced equation, the molar ratio of C₂H₂ to O₂ is 2:5.
Step 3: Calculate the number of moles of O₂ needed to react with 1.85 moles of C₂H₂
We will use the stoichiometric molar ratio.
1.85 mol C₂H₂ × (5 mol O₂/2 mol C₂H₂) = 4.63 mol O₂
about how much of the visible side of the moon is lit up during a full moon?
A. Three fourths
B. One fourth
C. None of it
D. All of it
Answer:
D
Explanation:
i learned this in elementary
HELP ASAP DUE IN 5 MINUTES WILL GIVE BRAINLIEST
Energy is conserved within a system, meaning that forms of energy are either transferred or transformed as they interact with objects. Which of the statements below correctly describe how energy is transferred or transformed in daily life?
Group of answer choices
Kinetic energy transforms into thermal energy when a heating pad is turned on.
Electrical energy is transferred into light energy so that a flashlight generates light when it’s turned on.
Chemical energy in food is transformed into mechanical energy as our body rides a bicycle down the street.
Nuclear energy is transferred to electrical energy to provide electricity for our homes.
Answer:
i do believe it is C. Chemical energy in food is transformed into mechanical energy as our body rides a bicycle down the street. but if i am wrong plz don't come at me but i believe that is right
Explanation:
Answer:
i do believe it is C. Chemical energy in food is transformed into mechanical energy as our body rides a bicycle down the street. but if i am wrong plz don't come at me but i believe that is right
Explanation:
Two models of the same compound are shown.
On the left labeled Model A 2 large overlapping black spheres with 3 small blue spheres overlapping the rear black sphere and 2 medium red spheres overlapping the front black sphere. One of the red spheres has a small blue sphere overlapping it. On the right labeled Model B 2 C's connected by a black line. The C on the left has 3 H's attached by 1 black line each and the C on the right has 2 Os attached to it. The top O is attached by 2 black lines and the bottom O by 1 black line. The bottom O also has an H attached to it by 1 black line.
In what way is Model A better than Model B?
Model A shows the types of elements in the compound, but Model B does not.
Model A shows the total number of atoms in the molecule, but Model B does not.
Model A shows the three-dimensional shape of the molecule, but Model B does not.
Model A shows the number of atoms of each element in the molecule, but Model B does not.
Answer: C. Model A shows the three-dimensional shape of the molecule, but Model B does not.
Explanation:
i took the test and it makes the most sence for the modeles.
A saturated hydrocarbon having molecular formula CnH2n+2 diffuses through a porous membrane twice as fast as sulphur dioxide. Calculate the volume occupied by the hydrocarbon at27°C and 2atm ?
Help me fast !
Answer:
12.3 L
Explanation:
Now we have that the rate of diffusion of the saturated hydrocarbon is R1
Rate of diffusion of sulphur dioxide is R2
Molar mass of hydrocarbon is M1
Molar mass of sulphur dioxide is 64 gmol-1
From Graham's law;
R1/R2 = √64/M1
2/1 =√64/M1
(2/1)^2 = (√64/M1)^2
4/1 = 64/M1
4M1 =64
M1 = 16
To obtain the number of moles of the gas;
(n*12) + (2n + 2) 1 = 16
12n + 2n + 2 = 16
14n + 2 = 16
14n = 16 - 2
n = 14/14
n = 1
Hence the hydrocarbon is CH4
Volume occupied by CH4 at STP = 22.4 L
Hence;
P1 = 1 atm
T1 = 273 K
V1 = 22.4 L
T2 = 300 K
P2 = 2 atm
V2 = ?
P1V1/T1 = P2V2/T2
P1V1T2 = P2V2T1
V2 = P1V1T2/P2T1
V2 = 1 * 22.4 * 300/2 * 273
V2 = 12.3 L
The volume occupied by the hydrocarbon at 27 °C and 2 atm is 12.31 L
Let the hydrocarbon be initially at standard temperature and pressure (STP)
Thus, we can obtain the new volume of the hydrocarbon by using the combined gas equation as illustrated below:
Initial volume (V₁) = STP = 22.4 L Initial pressure (P₁) = STP = 1 atmInitial temperature (T₁) = STP = 273 KFinal temperature (T₂) = 27 °C = 27 + 273 = 300 KFinal pressure (P₂) = 2 atmFinal volume (V₂) =?P₁V₁ / T₁ = P₂V₂ / T₂
(1 × 22.4) / 273 = (2 × V₂) / 300
22.4 / 273 = (2 × V₂) / 300
Cross multiply
273 × 2 × V₂ = 22.4 × 300
546 × V₂ = 6720
Divide both side by 546
V₂ = 6720 / 546
V₂ = 12.31 L
Thus, the volume occupied by the hydrocarbon at 27 °C and 2 atm is 12.31 L
Learn more about gas laws:
https://brainly.com/question/25967416
Please help....thank you
Answer:
a. volcanic changes create new land
PLEASE HELP WILL GIVE BRAINLIEST
Answer:
Coefficients represents no of moles while subscripts represent no of atoms.
Answer:
Coefficients came before formula . Example = 4CO means there are 4 molecules of carbonmonooxide.
Subscripts came after and below the formula . Example = Oxygen gas in which 2 is a subscript which means there are 2 atoms of Oxygen in 1 molecule of Oxygen i.e. oxygen gas
Which electron dot diagram represents H2?
Answer:
H:H
Explanation:
. A student adds 50 mL of Lead (II) Nitrate solution to 50 mL of potassium iodide. Each
solution is colorless, but when these two liquids are mixed, a yellow precipitate is
observed. What has most likely happened in the experiment?
Answer:
after the reaction between Lead (II) Nitrate solution and potassium iodide occur Lead(II) iodide was formed and it's yellow color.
Explanation:
Pb(NO3)2 + KI = KNO3 + PbI2
Question 1 / 1
Which of the following is a covalent bond?
A. CO2
B. NaCl
C. Fe2O,
Answer:
Chemistry deals with matter, and there is a tremendous variety of matter in the universe. The behavior of matter depends on the type of elements that are present and on the structure of those elements—how they are connected to make a molecule. In this exercise, you will evaluate some representative models to develop the rules used to classify a compound, to predict the formula of a compound, and to name the compound. This exercise is just the beginning of the work needed to be done to master the rules of writing formulas and nomenclature. Your textbook has tables of the names and formulas of common cations and anions, and discusses the rules of nomenclature in detail. You will need to spend some time with this material, as the formal rules of nomenclature may not be presented in lecture, although they will certainly be used in discussions of Lewis structures and reaction chemistry.
Explanation:
In a covalent compound, valence electrons are shared between the two atoms in the bond. These can be evenly shared (covalent bond) or unevenly shared (polar covalent bond). In an ionic bond, electrons are localized to one of the atoms (giving it an overall negative charge), while the other atom has an overall positive charge. The difference in electronegativity between the two atoms in the bond can help predict whether the bond is likely to be ionic, covalent, or polar covalent, as can the type of atoms involved (metals or non-metals). A bond with two identical atoms is always pure covalent, while a covalent bond with two different atoms is likely to be polar covalent.
Rosie balanced the equation below with the lowest coefficients, however she made a mistake.
2 AgCl + 2 Mg(NO3)2 --> 1 AgNO3 + 2 MgCl2
What was her error and what should the correct answer be?
Answer:
2 AgCl + Mg(NO3)2 --> 2AgNO3 + MgCl2
Explanation:
This is balanced equation
Spheres of Earth Assignment Active Analyzing Sphere Interactions Explain how Earth's spheres may be affected by the droughts brought on by El Niño. Sometimes, the surface of the Pacific Ocean warms up, causing changes in the weather in some areas. This phenomenon is called El Niño. El Niño causes the amount of rainfall in some parts of the United States and South America to increase. It also causes droughts to occur in Southeast Asia and Australia. Droughts occur when an area receives less rain than it normally does over a certain period.
help me on this question please. it is 7th grade science
In the reaction C + O2 → CO2, 18 g of carbon react with oxygen to produce 72 g of carbon dioxide. What mass of oxygen would be needed in the reaction?
18 g
54 g
72 g
90 g
Answer:
54g of O2 reacted in the reaction
Answer:
54g
Explanation:
A sample is in the second half-life. What percent of the sample is stable at this point?
A. 12.5%
B. 25%
C. 50%
D. 75%
Answer:
75%
Explanation:
on edg :)
which event would most likely lead to a thunderstorm giving brainliest
Answer:
A
Explanation:
Took at test on this and my teacher said it was right, hopefully I remembered right, also I answered ur other question like this I think lol