Answer:
#1: The law of conservation of mass underpins the principles of stoichiometry. Because matter cannot be generated or destroyed, the mass of each element present in a chemical reaction's product(s) must be equal to the mass of each element present in the reactant (s).
#2: 3molH2:2molNH3
Explanation:
Question 1:
Stoichiometry allows us to make predictions about the outcomes of chemical reactions. Making useful predictions is one of the main goals of science, the other being the ability to explain phenomena we observe in the natural world.According to the Law of Conservation of Mass, in "ordinary" chemical reactions, mass is neither created nor destroyedStoichiometry deals with the chemical quantities of a BALANCED chemical equations.The following is an example of an unbalanced equation and we can see why it does NOT follow the law of conservation of mass.H2O (l) ⇒ H2 (g) + O2 (g)From the equation above, it appears that you begin with 2 hydrogen atoms and form 2 hydrogen atoms. That's just fine. BUT, you cannot begin with 1 oxygen atom and end up with 2 oxygen atoms on the product. This is a violation of the Law of Conservation of Mass.Below, you will find the balanced equation for this reaction which DOES follow this law.2 H2O (l) ⇒ 2H2 (g) + O2 (g)In the above example, you begin with 4 hydrogen atoms and produce four hydrogen atoms; you start with 2 oxygen atoms and end with 2 oxygen atoms.The coefficients needed to balance this chemical equation tell you the ratios that the reactants and products exist in; stoichiometry deals with the quantities of balanced equations.---------------------------------------------------------------------------------------------------Question 2:
In order to determine the mole ratio, we need to begin with a balanced chemical equation.For this reaction the balanced chemical equation isN2 + 3H2 ⇒ 2NH3The mole ratios are determined using the coefficients of the substances in the balanced chemical equation.1 moln: 3mol2 : 2molNH3The mole ratios for each substance pair would be1molN2: 3molH21molH2/3molH2 or 3molH2/1molN21molN2:2molNH31molN2/2molNH3 or 2molNH3/1molN23molH2:2molNH33molH2/2molNH3 or 2molNH3/3molH2What percentage of carbon is in baking soda?
Answer:
14.297%
Explanation:
Answer:
14.297%
Explanation:
this is the percentage
Predict two differences in the physical properties of SiO2 and SiO4
Answer:
Answer 1) In the mixture of sand, NaCl and CaCO_{3}CaCO
3
first separation was done by dissolving the mixture in water. In the first step the NaCl will get dissolved whereas, CaCO_{3}CaCO
3
will be undissolved and sand will settle at the bottom. Here, the physical property of solubility of NaCl in water is taken into consideration. The collected water is then filtered off and evaporated to get the NaCl back from the mixture with some loss. No chemical change occurs in case of NaCl extraction from water.
Answer 2) When CaCO_{3}CaCO
3
was to be removed from the undissolved part. The chemical property of CaCO_{3}CaCO
3
was used. Where it gets dissolved in acidic medium. And this way we can extract CaCO_{3}CaCO
3
and remove sand from it. We change the chemical composition of CaCO_{3}CaCO
3
by adding HCl to the mixture and dissolve CaCO_{3}CaCO
3
to form CaCl_{2}CaCl
2
which gets dissolved into the solution of HCl. Here, first decantation occurs and then extraction is done. Second, extraction is done using potassium carbonate in it which separates CaCl_{2}CaCl
2
from sand.
Answer 3) Here, Unknown mixture of salt and sand weighed =7.52 g (before washing);
Unknown mixture of salt and sand weighed =3.45 g (after washing);
To calculate the amount of salt in it, we can simply subtract the values of before and after washing change in weights.
The property of NaCl being soluble in water it will go away with washing leaving behind the sand only, after washing.
So, Weight of salt was = 7.52g - 3.45 g = 4.07g
To find the percentage of sand that was mixed with salt =
(3.45 g sand / 7.52g of mixture) X 100 = 45.9% sand was mixed with salt.
To verify whether the correct percentage of salt and sand was calculated we can recheck the value for salt as well.
(4.07 g of salt / 7.52g of mixture) X 100 = 54.1% salt
On adding we get, 45.9% + 54.1% = 100%.
Which confirms that the calculations are correct.
Explanation:
Hope its Helps you ! : )
How does mechanical advantage help in doing work?
Answer:
Mechanical advantages allows humans to perform tasks much easier in terms of the force they need to apply, but must always obey the conservation of energy. Mechanical advantage is a measure of the ratio of output force to input force in a system, used to analyze the forces in simple machines like levers and pulleys.A good example is pushing a heavy object up a ramp. It may be easier to push the object up a ramp instead of just lifting it up to the right height, but it takes a longer distance.Explanation:
Hope it helps you!! why do vehicle engines produce nitrogen oxides
Answer:
When fuels are burned in vehicle engines, high temperatures are reached. At these high temperatures, nitrogen and oxygen from the air combine to produce nitrogen monoxide. When this nitrogen monoxide is released from vehicle exhaust systems, it combines with oxygen in the air to form nitrogen dioxide.
Explanation:
please mark me as brainlist pleaseExplanation:
Nitrogen and oxygen from the air combine at high temperatures in the engine to produce nitrogen (II) oxide by the reaction :
N2(g) + O2(g) → 2NO(g).
Nitric oxides rise in the atmosphere and are oxidized to nitrogen dioxide, NO2 which dissolves in the precipitating water to form acid rain.
Why is mtDNA so useful in forensic investigations?
Select all of the statements that correctly describe DNA structure:
Group of answer choices
The pyrimidine and purine bases are located on the outside of the double helix.
The sugars and phosphate groups are located on the exterior of the helix.
Base pairing will always be between a purine base and a pyrimidine base.
Two connected DNA strands will be oriented in the same direction.
Hydrogen bonds will hold two DNA strands together.
Answer:
Hydrogen bonds will hold two DNA strands together.The sugars and phosphate groups are located on the exterior of the helix.Base pairing will always be between a purine base and a pyrimidine base.I hope this helps you
:)
What led to a change in carbon dioxide in biodome files
Answer:
The decrease of decomposers. The decrease of decomposers led to a change in carbon dioxide in biodome files.
Name five elements that are gases.
Answer:
oxygenhydrogenchlorinenitrogenfluorineExplanation:
They are all gases at room temperature.
Hope this helps!
What is respiration explain in own words please
Answer:
The process in which we breathe out carbon dioxide and breathe in oxygen.
Explanation:
Carbon 14 has a half-life of 5,730 years. If one fourth as much carbon 14 is found in an ancient tree ring compared to the amount of carbon 14 found in a modern tree, how old can you calculate the tree to be?
First, let's recall the equation for half-life:
N(t) = [tex]N_{0}[/tex] · [tex]\frac{1}{2}^{\frac{t}{t_{1/2}}}[/tex]
Woah.
While we could certainly solve this question by using the half-life equation, it might be easier to just give this question some thought.
Half-life, is, essentially, the time it takes for radioactive material to be halved. For example, if something had a half-life of ten years and weighed 20 pounds, after ten years it would weigh 10 pounds and after another ten years would weigh 5 pounds, then 2.5, and so on. (Note that it never actually reaches 0! It keeps halving and halving over and over again, becoming smaller and smaller but never disappearing!)
In this question, we're given the half-life of Carbon-14 and asked how old a tree with 1/4 the amount of carbon-14 of a normal tree would be. Let's think about this question:
We can make the assumption that a "modern" tree is a tree that is 0 years old. Why? Well, it would make it painfully complicated if we assumed anything other than that, and your chemistry teacher wouldn't be that cruel (I hope).How many half-lives must the Carbon-14 go through for the amount to be 1/4? Since the amount halves every half-life, we can count on our fingers - one half-life will make the amount 1/2 the original, two half-lives will make the amount half the 1/2 amount, making it 1/4 the amount... hey! We got it!We figured out that it takes two half-lives for Carbon-14 to be 1/4 its original amount! Since the duration of a half-life never changes, we can simply multiply 5730 by 2 to find how many years it'd take to achieve two half-lives:
5730 · 2 = 11460
The tree is about 11,460 years old.
And we've solved it! (A quick tip - if you ever encounter a question like this again, you can quickly calculate the number of half-lives in your head depending on the amount remaining that they give you. Just keep halving the amount every half-life! One half-life is 1/2, two half-lives is 1/4, three is 1/8, four is 1/16, and so on and so forth)
If you have any questions about anything I explained here or need clarification on anything, just let me know! Good luck!
- breezyツ
ch4+2o2=co2+2h2o how many moles of methane are in 20 liters of methane?
how many moles of water are produced in this reaction?
Convert mole of water to grams
Show work please
Answer:
See below, please
Explanation:
1 mol CH4 ——＞2 mol H2O=2x18 g/mol= 36 g
The question is not clear. You should tell us the concentration of CH4, methane.
Reaction
CH₄ (g) + 2O₂ (g) <=> CO₂ (g) + 2H₂O(g)
assume at STP ( 1 mole gas = 22.4 L)
for 20 L, moles of methane:
= 20 : 22.4 = 0.893
moles of water = 2/1 x mol methane = 2/1 x 0.893 = 1.786
mass of water = mol x molar mass = 1.786 x 18 g/mol = 32.148 g
At a certain temperature and pressure, chlorine (cl2) molecules have an average velocity of 0. 0380 m/s. What is the average velocity of sulfur dioxide (so2) molecules under the same conditions?
[tex]\longrightarrow[/tex]From the kinetic molecular theory of gases, the average speed of gas molecules at a specific temperature and pressure is given by :-
[tex]\green{ \underline { \boxed{ \sf{v_{avg} = \frac{8RT}{\pi M}}}}}[/tex]
where
R = 8.314 J/mol, the universal gas constant T is the absolute temperature of the gas M is the molar mass of the gas.[tex]\longrightarrow[/tex]For two different gases A and B at the same temperature, it can be shown that the average speeds are inversely proportional to the square root of their molecular masses-
[tex]\green{ \underline { \boxed{ \sf{ \frac{v_{avg} ^A}{v_{avg}^B} = \sqrt{\frac{M_A}{M_B}}}}}}[/tex]
Given:-[tex]\sf average \:velocity \:of \:Cl_2,v_{avg} ^B= 0.0380 \:m/s [/tex]
Now,
[tex]\sf Molar \:mass \:of \:Cl_2 = 2\times atomic \:mass \:of \:Cl[/tex]
[tex]\implies[/tex][tex]\sf Molar \:mass \: of \:Cl_2 = 2\times 35.5[/tex]
[tex]\implies[/tex][tex]\sf Molar \:mass \:of \: Cl_2 = 71 \:g[/tex]
similarly,
[tex]\begin{gathered}\\\implies\quad \sf Molar \: mass \:of \: SO_2 = atomic \:mass \:of \:S +2\times \: atomic \: mass \: of \: O \\\end{gathered} [/tex]
[tex]\begin{gathered}\\\implies\quad \sf 32 +2\times 16 \\\end{gathered} [/tex]
[tex]\begin{gathered}\\\implies\quad \sf 32 +32 \\\end{gathered} [/tex]
[tex]\begin{gathered}\\\implies\quad \sf 64 \\\end{gathered} [/tex]
Putting Values in formula to get average velocity -
[tex]\begin{gathered}\\\implies\quad \sf { \frac{v_{avg} ^{SO_2}}{v_{avg}^{Cl_2}} = \sqrt{\frac{M_{SO_2}}{M_{Cl_2}}}}\\\end{gathered} [/tex]
[tex]\begin{gathered}\\\implies\quad \sf { \frac{v_{avg} ^{SO_2}}{0.0380} = \sqrt{\frac{71}{64}}}\\\end{gathered} [/tex]
[tex]\begin{gathered}\\\implies\quad \sf \frac{v_{avg} ^{SO_2}}{0.0380} = 1.05 \: \\\end{gathered} [/tex]
[tex]\begin{gathered}\\\implies\quad \sf v_{avg} ^{SO_2}= 1.05 \times 0.038 \: \\\end{gathered} [/tex]
[tex]\begin{gathered}\\\implies\quad \sf v_{avg} ^{SO_2} = 0.4 \: m/s\: \\\end{gathered} [/tex]
[tex]\longrightarrow[/tex]Thus the average velocity of sulphur dioxide molecules under the same conditions is 0.4 m/s
Which aspect does a light year measure?
O distance
O speed
O curvature of space
O time
A light-year is the distance a beam of light travels in a single Earth year. so it is A distance
Give me brainliest
In the graphic, X represents which
element?
12
6
2x
А
12
Magnesium
18
Argon
Ar
6
Carbon
С
Mg
The element which X represents in the given graphic is Carbon
Determining the identity of an elementFrom the question, we are to determine the element in which X represents
Comparing the given graphic with the atomic notation shown in the attachment, X has a mass number of 12 and an atomic number of 6
The element which has a mass number of 12 and an atomic number of 6 is Carbon.
Hence, the element which X represents in the given graphic is Carbon.
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For an atom to be neutral, it must have the same number of electrons as what other particle
A. Protons
B. Atomic mass
C. Neutrons
D. Photons
Answer:
A. Protons
Explanation:
For an atom to be neutral, it must have the same number of electrons as protons. Since protons are positive and electrons are negative, that will result in a neutrally charged atom.
hope this helps!! p.s. i really need brainliest :)
What is the value for Delta*G at 500 K if Delta*H = 27kJ / m * o * l and triangle S=0.09 kJ/(mol* K) ? OC. Delta*G = 26.9kJ / m * o * l OB. Delta*G = - 18kJ / m * o * l O D. Delta*G = 0kJ / m * o * l OA. Delta*G = 72kJ / m * o * l
The value of the Gibbs free energy (ΔG) for the reaction given in the question is –18 KJ/mol
Data obtained from the question Temperature (T) = 500 KEnthalpy change (ΔH) = 27 KJ/mol Change in entropy (ΔS) = 0.09 KJ/Kmol Gibbs free energy (ΔG) =? How to determine the Gibbs free energyThe Gibbs free energy (ΔG) can be obtained by using the following equation as illustrated below:
ΔG = ΔH – TΔS
ΔG = 27 – (500 × 0.09)
ΔG = 27 – 45
ΔG = –18 KJ/mol
Thus, the value of ΔG for the reaction is –18 KJ/mol
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the effect that the environment has on the learning of an organism is called
A. Law of motion
B. Hilberts function
C. Law of effect
D. Kopps law
WILL GIVE BRAINLIST
If a certain species is found to have DNA composed of 17% cytosine, what would be the percentages of the other three bases?
Adenine = %
Thymine = %
Guanine = %
Enter only a number/numeral in each provided box.
Answer:
Adenine=33%
Thymine=33%
Guanine=17%
Explanation:
the base pairs percentages must be the same
Water and liquid HF are good solvents for many ionic salts. However, oils and waxes with structures such as shown in the accompanying Lewis structure do not dissolve in water. Explain why.
Answer:
water and liquid HF are polar solvents, hence they disslove polar solutes like ionic salts
Waxes and Oil however are non polar solvents, hence they dissolve non polar solutes.
As a general law; Polar solvent dissolves polar solute. Non polar solvent dissolves non polar solutes
What are the four abbreviations that are used to show the states of substances in chemical reactions?
How is anaerobic respiration helpful to you as and individual or society please answer I really need help with this don’t answer for points because I will report!!
Answer:
Anaerobic exercise uses energy that’s readily available in your muscles, because the body isn’t relying on oxygen, these strong, powerful movements can only be sustained for 10 to 15 seconds.
Explanation:
Anaerobic exercise is beneficial for good health because it:
Strengthens bones
Burns fat
Builds muscle
Maintains muscle mass, which is important for people as they age
As we age, we tend to lose muscle at a rate of about 1 percent per year after age 27, unless we actively work to slow that decline, Muscle is a metabolically active tissue and the more of it we can maintain, the more calories we can burn while at rest.
Anaerobic respiration occurs more quickly than aerobic respiration.
A major advantage of aerobic respiration is the amount of energy it releases. Without oxygen, organisms can split glucose into just two molecules of pyruvate. This releases only enough energy to make two ATP molecules.
Methanogenesis, a form of carbon-dioxide respiration, that is used to produce methane gas by anaerobic digestion. Biogenic methane is used as a sustainable alternative to fossil fuels.
Anaerobic respiration is a critical component of the global nitrogen, iron, sulfur, and carbon cycles through the reduction of the oxyanions of nitrogen, sulfur, and carbon to more-reduced compounds.
Specific types of anaerobic respiration are also critical in bioremediation, which uses microorganisms to convert toxic chemicals into less-harmful molecules to clean up contaminated beaches, aquifers, lakes, and oceans. For example, toxic arsenate or selenate can be reduced to less toxic compounds by various anaerobic bacteria via anaerobic respiration.
Hope you will find it helpful. I tried my best. Thank you.
what room in a house is similar to the chloroplast in a cell?
Answer:
kitchen
Explanation:
Chloroplast help to trap light energy from the sun which in turn is used to generate energy for the cell, likewise kitchen holds the materials that are required for cooking food which when taken gives the body energy as well.
(1)
(c) A teacher puts hot sodium into a gas jar of chlorine.
The changes seen before, during and after this reaction were observed.
Complete the sentences.
Choose the answers from the box.
colourless
green
lilac
silver
white
yellowlorange
Sodium is a
solid.
Chlorine is a
gas.
The hot sodium burns with a
flame.
The product sodium chloride is a
solid.
(4)
Answer:
(1)
(c) A teacher puts hot sodium into a gas jar of chlorine.
The changes seen before, during and after this reaction were observed.
Complete the sentences.
Choose the answers from the box.
colourless
green
lilac
silver
white
yellowlorange
Sodium is a
solid.
Chlorine is a
gas.
The hot sodium burns with a
flame.
The product sodium chloride is a
solid.
1. slivery-white
2. yellow
3. lilac
4. colourless
Explanation:
Deadline homework if someone could this I make u a brainlist. Thanks
Answer:
material a
Explanation:
it is expensive which means it's better quality
it's easy to make so you will be able to make lots and then make more money to buy more material
I need help with this please
Answer:
really?!
Explanation:
this is a test your suppose to answer it
If you weighed out 22 grams of Al2O3 on a scale, how many moles of Al2O3 is that? Show your work.
Answer: Point nine six grams per mole which are often just written G / mo L and that's the molar mass or molecular weight for al2o3 aluminum oxide.
Explanation:
A chemist pours 500 mL of a 3.0000 molar solution of sodium hydroxide into a 3.0000 liter volumetric flask and fills the flask up with
water. What is the molarity of the new solution?
M1V1 = M2V2
M1 = 3.000 M
V1 = 0.8000 L
M2 = ?
V2 = 2.00 L
M2 = M1V1/V2 = (3.000 M)(0.8000 L)/(2.00 L) = 1.20 M
A chemist pours 500 mL of a 3.0000 molar solution of sodium hydroxide into a 3.0000 liter volumetric flask and fills the flask up with water. 1.20 M is the molarity of the new solution.
What is molarity?Molarity is also known as concentration in terms of quantity, molarity, or substance. It is a way to gauge how much of a certain chemical species—in this case, a solute—is present in a solution. It refers to a substance in unit volume for solution in terms of quantity.
The amount of moles / litre is the molarity unit that is most frequently used in chemistry. One mol/L of a solution's concentration is referred to as its molarity. It is frequently abbreviated as 1 M. When one gramme of solute dissolves in one litre of solution, the solution has a molarity of one.
M1V1 = M2V2
M1 = 3.000 M
V1 = 0.8000 L
M2 = ?
V2 = 2.00 L
M2 = M1V1/V2 = (3.000 M)(0.8000 L)/(2.00 L) = 1.20 M
Therefore, 1.20 M is the molarity of the new solution.
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Burning hydrogen is an example of a chemical reaction. The reaction is
shown in the diagram. Which of the following sthtements about energy in
this reaction is the most accurate?
A sample of gas has an initial volume of 20 L and an initial pressure of
2.5 atm. If the pressure changes to 3.1 atm, what is the new volume, as-
suming that the temperature remains constant?
Show your work.
The new volume of the gas is 16.3 L.
Boyle's lawBoyle's law states that the volume of a fixed mass of gas is inversely proportional to its pressure, at a constant temperature.
To calculate the new volume of the gas, we use the expression from Boyle's law.
Formula:
PV = P'V'............. Equation 1Where:
P = initial pressure of gasV = Initial volume of gasP' = Final pressure of gasV' = Final volume of gasMake V' the subject of the equation
V' = PV/P'............. Equation 2From the question,
V = 20 LP = 2.5 atmP' = 3.1 atmSubstitute these values into equation 2
V' = (20×2.5)/3.1V' = 16.13 L.Hence, The new volume of the gas is 16.3 L.
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Somebody help me this pleaseeeeee
༎ຶ‿༎ຶ
Answer:
1.the highest point of the wave is the crest while lowest point is trough.
2.?
3. wave length
4. frequency
5. A is crest b is trough c is amplitude and d is wave length
7.a = this is longitudinal wave, b no = letter h represents a compression and letter I represents rarefactions , letter g represents a wave length.
8 . in transverse wave
9. longitudinal wave
10. longitudinal wave
11. transverse wave
12. ?