Answer:
Option D. The number of oxygen atom is the same before and after the reaction.
Explanation:
From the question given above, the following were obtained:
Robin's equation:
H₂ + O₂ —> H₂O
Alex's equation
2H₂ + O₂ —> 2H₂O
To know which equation better represents the reaction, we shall determine which of the equation is balanced.
For Robin:
H₂ + O₂ —> H₂O
Element >>> Reactant >>> Product
H >>>>>>>>> 2 >>>>>>>>>> 2
O >>>>>>>>> 2 >>>>>>>>>> 1
Robin's equation is not balanced because the number of atoms of each element in the reactant and product are not equal.
For Alex:
2H₂ + O₂ —> 2H₂O
Element >>> Reactant >>> Product
H >>>>>>>>> 4 >>>>>>>>>> 4
O >>>>>>>>> 2 >>>>>>>>>> 2
Alex' equation is balanced because the number of atoms of each element in the reactant and product are equal.
Thus, option D gives the right answer to the question.
How many atoms are in 57.5 liters of xenon gas at STP
Answer:
1.55 × 10²⁴ atoms Xe
General Formulas and Concepts:
Atomic Structure
Reading a Periodic TableMolesSTP (Standard Conditions for Temperature and Pressure) = 22.4 L per mole at 1 atm, 273 K Avogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.Stoichiometry
Using Dimensional AnalysisExplanation:
Step 1: Define
[Given] 57.5 L Xe at STP
[Solve] atoms Xe
Step 2: Identify Conversions
[STP] 22.4 L = 1 mol
Avogadro's Number
Step 3: Convert
[DA] Set up: [tex]\displaystyle 57.5 \ L \ Xe(\frac{1 \ mol \ Xe}{22.4 \ L \ Xe})(\frac{6.022 \cdot 10^{23} \ atoms \ Xe}{1 \ mol \ Xe})[/tex][DA] Divide/Multiply [Cancel out units]: [tex]\displaystyle 1.54583 \cdot 10^{24} \ atoms \ Xe[/tex]Step 4: Check
Follow sig fig rules and round. We are given 3 sig figs.
1.54583 × 10²⁴ atoms Xe ≈ 1.55 × 10²⁴ atoms Xe
If 2.00 moles of H2 and 1.55 moles of Oz react how many moles of H20
can be produced in the reaction below?
2 H2(g) + O2(g) → 2 H2O(g)
why are ionic compound soluble in water
Answer:
Most ionic compounds are soluble in water. Polar water molecules have a strong attraction for charged ions and the charged ions become solvated as they dissociate into water and ionic compounds are soluble in water.
How many grams are present in 3.4
moles of CH2COOH?
Show all work
Answer:
m = 200.6 gr
Explanation:
CH2COOH : n = 3.4 mol
Mr = 12 + 2 + 12 + 2×16 + 1 = 59
n= m / Mr => m = n× Mr => m = 3.4×59 => m = 200.6 gr
Question 2
1 pts
r
A compound is 31.1 % S, the rest is chlorine. The compound has a molecular mass of 205.94 amu.
What is its molecular formula?
Explanation:
its hard to explain unless we know what the question fully asks..
Imine formation from an aldehyde and an amine proceeds reversibly under slightly acidic conditions. The reaction is reversible due to acid-catalyzed hydrolysis of the imine. Imine formation generates an equivalent of water. Given these facts, explain why the imine can be isolated from the reaction mixture.
Answer:
Imine can be isolated from the reaction mixture as water is continuously removed from the reaction chamber
Explanation:
In this reaction, a non -aqueous solvent is not used (not mentioned in the question). Thus, we can say that there is continuous removal water under suitable reacting conditions and hence the imine formed is left behind.
Dawn is comparing how different animals move and the structures they use to move. She made the table shown below.
Animal Method of movement Structures used for movement
panther walks legs and feet
parrot flies wings
shark swims
Which structure completes the table for the shark?
eyes and brain
skin and scales
tail and fins
teeth and jaws
Answer:
tail and fins
Explatanation:
Steve and Meg are doing an experiment where they need to make 37 grams of Fe2O3. How many grams of Fe would they need ?
Answer:
25.9g
Explanation:
Molecular mass of Fe₂O₃ = (56 * 2) + (16 * 3)
= 112 + 48 = 160
Let's follow the unitary method now
In 160g Fe₂O₃ , there is 112 g Fe
In 1 g Fe₂O₃ , there is 112 / 160 g Fe
In 37 Fe₂O₃ , we need 112 * 37 / 160
= 25.9 g Fe
The most common experimental technique to perform elemental analysis is combustion analysis, where a sample is burned in a large excess of oxygen and the combustion products are trapped in a variety of ways. A 99.99% pure, 0.4808 g sample containing only carbon, hydrogen, and nitrogen is subjected to combustion analysis, resulting in the formation of 0.6859 g CO2, 0.6973 g H2O, and 0.4646 g NO. What is the empirical formula of the sample
Answer:
C₂H₅N₂
Explanation:
In the combustion analysis, all NO comes from the nitrogen of the sample, that means:
Moles NO = Moles N in the sample
In the same way:
Moles CO2 = Moles C in the sample
Moles H2O = 1/2 moles H in the sample
To solve this problem we must convert the mass of each gas to moles in order to find the moles of each atom. The empirical formula is the simplest whole number ratio of atoms presents in the molecule:
Moles NO = N -Molar mass: 30g/mol
0.4646g * (1mol / 30g) = 0.01549 moles N
Moles CO2 = C -Molar mass: 44.01g/mol-
0.6859g * (1mol / 44.01g) = 0.01559 moles C
Moles H2O = 1/2moles H -Molar mass: 18.02g/mol-
0.6973g * (1mol / 18.02g) = 0.03870 moles H
The ratio of atoms is -Dividing in the low number of moles = moles N-:
C = 0.01559 / 0.01549 = 1
N = 0.01549 / 0.01549 = 1
H = 0.03870 / 0.01549 = 2.5
Twice this ratio of atoms -Because empirical formula must be given only with whole numbers:
C = 2
N = 2
H = 5
The empirical formula is:
C₂H₅N₂Students can demonstrate reflection by doing which of the following?
A Warming metal under a heat lamp.
B. Observing their own image in still water.
C. Enlarging an image using a hand lens.
0
D. Measuring a shadow made by the Sun.
Answer:
a
Explanation:
Why does understanding the Rock Cycle help us to plan living on the ocean? answer before it's too late!
Answer:
Learning the rock cycle and understanding the processes involved helps all of us. This is how soil forms, through the breakdown of rocks. We need soil to survive—imagine trying to grow vegetables without it. This is an immediate connection to the food chain
D = 22.1 g/cm3, M = 523.1 g, V = ? mL
Answer:
The volume is 22.66 mL
Explanation:
D = 22.1 g/cm³, M = 523.1 g, V = ? mL
For Volume
Density = Mass ÷ Volume
Volume = Mass ÷ Density
V = M ÷ D
V = 523.1 g ÷ 22.1 g/cm³
V = 23.66 cm³
Now, 1 cm³ = 1 mL
So,
V = 22.66 mL
Thus, The volume is 22.66 mL
-TheUnknownScientist
heat would best be transferred by conduction between
A. a candle and the air
B. an oven and a glass dish
C. a stove and a copper pot
D. water and a wooden spoon
Answer:
C. or B.
Explanation:
The reason I chose c best, is when your cooking something with a pot with food in it max heat in about 5 minutes, the handle starts to get warmer every minute. This is conduction, where the heat transfers from the very bottom all the way to the very edge of something that is heated at a certain temperature.
How many molecules of carbon tetrafluoride, CF4, are in 176 grams of CF4?
Answer:
1.2*10^24 molecules of CF4
Explanation:
the molar mass of cf4 is 88.0043 g/mol
176/88.0043 = 2 moles of CF4
Then multiply by avogadro's number (6.022*10^23) to get the number of molecules
2*6.022*10^23 = 1.2*10^24 molecules of CF4
There are 1.204 × 10²⁴ molecules of carbon tetrafluoride in 176 grams of CF4.
HOW TO CALCULATE NUMBER OF MOLECULES:
The number of molecules in a substance can be calculated by multiplying the number of moles in the substance by Avogadro's number:no. of molecules = no. of moles × 6.02 × 10²³The number of moles in CF4 can be calculated as follows:moles of CF4 = mass of CF4 ÷ molar mass of CF4. Molar mass of CF4 = 12 + 19(4)Molar mass of CF4 = 88g/molmoles of CF4 = 176g ÷ 88g/molmoles of CF4 = 2molNo. of molecules = 2 × 6.02 × 10²³no. of molecules = 12.04 × 10²³no. of molecules = 1.204 × 10²⁴ Therefore, there are 1.204 × 10²⁴ molecules of carbon tetrafluoride in 176 grams of CF4.Learn more at: https://brainly.com/question/11815186?referrer=searchResults
Hi can someone please help me with this. I would really appreciate it. It’s kind of urgent. Thank u so much!
Answer:
a) The system is in equilibrium
b) No other force is acting on the system
Explanation:
a) The forces in a system is balanced until and unless there is equal and opposite force acting on the system. In this image the upward force is equal to the downward force on the book and the table and hence it is in equilibrium
b) An object which is in static mode, produces downward force because of weight and in response to that a normal reaction is produced in upward direction. Apart from these two forces, no other force is acting on this book and table system.
A 31.25 mL aliquot of weak base that has a concentration of 0.683 M will be titrated with 0.434 M HCl. Calculate the pH of of the solution upon neutralization of half of the weak base. The Kb of the base is 1.5×10-6.
Answer:
pH = 8.18
Explanation:
The weak base, X, reacts with HCl as follows:
X + HCl → HX⁺ + Cl⁻
Where 1 mole of X with 1 mole of HCl produce 1 mole of HX⁺ (The conjugate acid of the weak base).
Now, using H-H equation for bases:
pOH = pKb + log [XH⁺] / [X]
Where pOH is the pOH of the buffer (pH = 14 -pOH)
pKb is -log Kb = 5.824
And [X] [HX⁺] are the molar concentrations of each specie
Now, at the neutralization of the half of HX⁺, the other half is as X, that means:
[X] = [HX⁺]
And:
pOH = pKb + log [HX⁺] / [X]
pOH = 5.824 + log 1
pOH = 5.824
pH = 14-pOH
pH = 8.18IM GIVING 100 POINTS FOR WHOEVER ANSWERS THIS PLS HELP determine which heat transfers below are due to the process of conduction. I) You walk barefoot on the hot street and it burns your toes. II) When you get into a car with hot black leather seats in the middle of the summer and your skin starts to get burned when you touch the seats. III) A flame heats the air inside a hot air balloon and the balloon rises. IV) A boy sits to the side of a campfire. He is 10 feet away, but still feels warm. Question 1 options: I & II III & IV I, II, & IV II, III, IV
Answer:
I and II
Explanation:
A gas cylinder initially contains 463 L of gas at a pressure of 159 atm. If the final volume of gas is 817 L, what is the final pressure?
Answer:
The final pressure is 90.1 atm.
Explanation:
Assuming constant temperature, we can solve this problem by using Boyle's Law, which states:
P₁V₁=P₂V₂Where in this case:
P₁ = 159 atmV₁ = 463 LP₂ = ?V₂ = 817 LWe input the given data:
159 atm * 463 L = P₂ * 817 LAnd solve for P₂:
P₂ = 90.1 atmThe final pressure is 90.1 atm.
What is the mass in grams of precipitate formed when 250.0 mL of 0.360 M ZnCl₂ is mixed with excess KOH in the following chemical reaction?
ZnCl₂ (aq) + 2 KOH (aq) → Zn(OH)₂ (s) + 2 KCl (aq)
Answer:
8.95 g
Explanation:
ZnCl₂ (aq) + 2 KOH (aq) → Zn(OH)₂ (s) + 2 KCl (aq)First we calculate how many ZnCl₂ moles reacted, using the given concentration and volume:
250 mL / 1000 = 0.250 L0.360 M * 0.250 L = 0.090 mol ZnCl₂Then we convert ZnCl₂ moles into Zn(OH)₂ moles [ Zn(OH)₂ is the precipitate, as it is the solid]:
0.090 mol ZnCl₂ * [tex]\frac{1molZn(OH)_2}{1molZnCl_2}[/tex] = 0.090 mol Zn(OH)₂Finally we convert 0.090 Zn(OH)₂ moles into grams, using its molar mass:
0.090 mol Zn(OH)₂ * 99.424 g/mol = 8.95 gThe mass of a substance is the product of the molar mass and the moles of the substance. The mass of precipitate formed in the reaction is 8.95 gm.
What is Mass?The mass of the substance is the weight of the compound or the molecule present in the sample.
The balanced chemical reaction is shown as:
[tex]\rm ZnCl_{2} (aq) + 2 KOH (aq) \rightarrow Zn(OH)_{2} (s) + 2 KCl (aq)[/tex]
Given,
Volume (V) of zinc chloride = 0.250 L
Molarity of zinc chloride (M) = 0.360M
Moles of zinc chloride are calculated as:
[tex]\begin{aligned} \rm moles &= \rm molarity \times volume \\\\&= 0.360 \times 0.250\\\\&= 0.090 \;\rm mol\end{aligned}[/tex]
Moles of zinc hydroxide from zinc chloride are calculated as:
[tex]0.090\;\rm mol \; ZnCl_{2} \times \dfrac{ 1\;\rm mol \;\rm Zn(OH)_{2}}{1\;\rm mol\; ZnCl_{2}} = 0.090 \;\rm mol[/tex]
Mass is calculated as:
[tex]\begin{aligned} \rm mass &= \rm moles \times molar \; mass\\\\&= 0.090 \times 99.424 \\\\&= 8.95 \;\rm gm\end{aligned}[/tex]
Therefore, 8.95 gm precipitate is formed.
Learn more about mass here:
https://brainly.com/question/13834164
Solid A at 80°C is immersed in liquid B at 60°C. Which statement correctly describes the energy changes between A and B?
Heat energy will be released by solid A which will then be absorbed by liquid B.
What is heat energy?
These little particles vibrate back and forth or run into each other constantly. All matter contains a type of energy known as heat (or thermal) energy, which is produced by the movement of particles.
Particle energy increases with temperature. It is possible for some of this energy to be transferred to cooler particles. For instance, in the gas state, when a fast-moving particle strikes a slower-moving particle, some of the energy from the collision is transferred to the slower-moving particle, increasing its speed.
A region of high energy will gradually spread throughout the material as a result of billions of moving particles colliding with one another until thermal equilibrium is established.
Therefore, heat energy will be released by solid A which will then be absorbed by liquid B.
Read more about heat energy, here
https://brainly.com/question/20038450
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please help illl mark brainlst (no links)
seafloor spreading allows the new formation of rock by:
A ) New rocks floating to the surface of the crust.
B ) The oceanic plates hit each other causing new rocks to fall off.
C ) Magma cooling on the crust.
D ) Seafloor spreading does not create new rocks.
Answer:
A ) New rocks floating to the surface of the crust.
TRUST
What causes a blue block to appear blue in the sunlight?
Group of answer choices
the blue block reflects all blue light and absorbs all other light
the blue block absorbs blue light and reflects all other light
only blue light is refracted and all other light is absorbed into the block
only blue light transmits through the block and all other light is reflected
Answer:
sadgsddagd
Explanation:
how are you doing?
The reduction of iron(III) oxide () to pure iron during the first step of steelmaking, ()()() is driven by the high-temperature combustion of coke, a purified form of coal: ()()() Suppose at the temperature of a blast furnace the Gibbs free energies of formation of and are and , respectively. Calculate the maximum mass of pure iron that can be produced by the combustion of of coke. Round your answer to significant digits.
Answer:
hello your question is incomplete attached below is the complete question
answer : To 2 significant digits = 5500 kg
Explanation:
Given
C(s) + O2 (g) ----------> CO2 ( g )
mass of CO2 = 8.9 * 10^6 g
number of moles = 8.9 * 10^6 / 12 = 7.416 * 10 ^5 mol
same amount of moles is needed by O2 hence
attached below is the detailed solution
Write a scientific explanation that answers the following question: Is matter conserved during a
chemical reaction in both closed and open systems?
Claim:
Evidence:
Reasoning:
Answer:
Matter is conserved during all chemical reactions because matter cannot be created or destroyed.
Explanation:
How many grams of hydroxide pellets, NaOh are required to prepare 50.0ml of a 0.150 M solution ?
A.0.300g
B.3.00g
C.2.00g
D.200.g
E. 0.025 M
Help (also tell me what the phenotype and genotypes are)
Answer:
genotype are the organism's hereditary information for example DNA
phenotype are the organism's physical characteristics for example your eyes or hair
or how your nose looks
Question 10
Which of the following fuels is most likely to perform poorly in cold climates?
A. Petrol
B. Petrodiesel
C. Biodiesel made from plant oil.
D. Biodiesel made from animal fat.
Answer:
C. Biodiesel made from plant oil.
Explanation:
The type of vegetable oil used in production greatly affects the performance of biodiesel in the winter. The less saturated the fat, the better the performance in winter time. Canola oil works very well for low temperature biodiesel, and palm oil is among the worst for cold weather performance.
Hope this helped!!!
Is lighting a match a chemical change?
Answer:
yes
Explanation:
Lighting a match and letting is burn is an example of a chemical change.
Matches use sulfur, phosphate and a friction agent held together by a binding agent. Together, the oxygen and sulfur burn slowly, igniting the wood of the match for a flame that lasts long enough to see by, light a candle or ignite a campfire.
According to the data, which part is described by the letter K?
a
constellation
b
galaxy
c
meteoroid
d
planet
Answer:
C meteoroid
Explanation:
Meteoroids are the only ones of the four that are under a kilometer in size.
For the wild type (unmutated) enzyme, you measure a rate of p-nitrophenol release by the change in absorbance at 405 nm (for the slower phase only) of 0.216 (in a cuvette with a pathlength of 1 cm) over the course of two minutes. Use the Beer-Lambert Law to calculate the concentration of product released over this time; the extinction coefficient of p-nitrophenol at 405 nm is 18,000 M-1 cm-1.
Answer:
1.2x10⁻⁵M = Concentration of the product released
Explanation:
Lambert-Beer's law states the absorbance of a solution is directly proportional to its concentration. The equation is:
A = E*b*C
Where A is the absotbance of the solution: 0.216
E is the extinction coefficient = 18000M⁻¹cm⁻¹
b is patelength = 1cm
C is concentration of the solution
Replacing:
0.216 = 18000M⁻¹cm⁻¹*1cm*C
1.2x10⁻⁵M = Concentration of the product released