Answer:
24.5g
Explanation:
Given parameters:
Mass of oxygen gas = 21.8g
Unknown:
Mass of water = ?
Solution:
This problem deals with the decomposition of water;
Reaction equation;
2H₂O → 2H₂ + O₂
2 mole of water will produce 1 mole of oxygen gas
First find the number of mole of the oxygen gas given;
Number of moles = [tex]\frac{mass}{molar mass}[/tex]
molar mass of O₂ = 2(16) = 32g/mol
Number of moles of O₂ = [tex]\frac{21.8}{32}[/tex] = 0.68moles
1 mole of oxygen gas will be produced from 2 mole of water
0.68moles of oxygen gas will be produce from 0.68 x 2 moles of water; = 1.36moles of water
Mass of water = number of moles x molar mass
Molar mass of water = 2(1) + 16 = 18g/mol
Mass of water = 1.36 x 18 = 24.5g
What is the pH of an aqueous solution made by combining 35.01 mL of a 0.3791 M ammonium chloride with 40.07 mL of a 0.3542 M solution of ammonia to which 3.112 mL of a 0.0896 M solution of HCI was added?
Answer:
pH = 9.25
Explanation:
Using H-H equation:
pH = pKa + log [A⁻] / [HA]
Where pH is pH of the buffer
pKa is pKa of the weak acid: 9.24
[A⁻] could be taken as moles of the conjugate base: Moles NH₃
[HA] moles of the weak acid: NH₄⁺
Initial moles of NH₃:
40.07mL = 0.04007L * (0.3542mol / L) = 0.01419mol
Initial moles NH₄⁺:
0.03501L * (0.3791mol / L) = 0.01327 mol
The HCl added reacts with NH₃ producing NH₄⁺:
HCl + NH₃ → NH₄⁺ + Cl⁻
Moles of HCl:
3.112x10⁻³L * (0.0896mol / L) = 0.00028 moles
That means moles of NH₃ and NH₄⁺ after the addition of HCl are:
NH₄⁺: 0.01327moles + 0.00028moles = 0.01355 moles
NH₃: 0.01419mol - 0.00028 moles = 0.01391 moles
pH of the buffer is:
pH = pKa + log [A⁻] / [HA]
pH = 9.24 + log [0.01391 moles] / [0.01355 moles]
pH = 9.25Given the composition of your food, which of the following is good for your health? WHICH OF THEM IS BAD?
Answer:Eating the right foods can help your body cope more successfully with an ongoing illness. ... corn syrup) are also bad for long-term health, especially in people with diabetes. ... Also, you may have nutritional deficiencies due to certain health or life conditions, such ... Eating a balanced diet can help prevent these conditions.
Explanation:
DONT SKIPP What type of bond will occur between lithium and bromine?
A.
these atoms will not bond
B.
metallic
C.
ionic
D.
covalent
Which type of bond stores the most energy
Answer:
I'm not sure which bond stores the most energy but the ionic bond is stronger than the covalent bond.
Explanation:
how many grams of oxygen would we need to consume to produce 13.9 grams of MgO
Answer:
5.56g
Explanation:
Expression of the equation:
2Mg + O₂ → 2MgO
Mass of MgO = 13.9g
Solution:
2Mg + O₂ → 2MgO
To solve this problem, let us find the number of moles of MgO from the given mas;
Number of moles = [tex]\frac{mass}{molar mass}[/tex]
molar mass of MgO = 24 + 16 = 40g/mol
Number of moles = [tex]\frac{13.9}{40}[/tex] = 0.35mole
Now,
2 moles of MgO is produced from 1 mole of oxygen gas
0.35 mole of MgO will be produced from [tex]\frac{0.35}{2}[/tex] mole of oxygen gas
= 0.17mole of oxygen gas
So;
Mass of oxygen gas = number of moles x molar mass
Molar mass of O₂ = 2(16) = 32g/mol
Mass of oxygen gas = 0.17 x 32 = 5.56g
Which of these describes a chemical property? A. the color of the substance B. the hardness of the substance C.how the substance behaves in the presence of an acid D. how the substance behaves in the presence of a magnet
Answer:
C. How the substance behaves in the presence of an acid.
Explanation:
Have a great day
Chemical properties can be defined as the ones that describe a substance's ability to undergo chemical changes.
Physical properties can be defined as the ones that are measured and observed without actually changing the substance's identity.
Among the given options, the color, the hardness, and the behavior of a substance in the presence of a magnet are all examples of physical properties.
However, the behavior of a substance in the presence of an acid is an example of chemical property.
Hence, the correct answer is option c.
https://brainly.com/question/1728902
Calculate the mass (in kg) of 4.87 x 10 25 atoms of Zn
Answer:
5.29kg
Explanation:
5.29kg
The mass of 4.87×10²⁵ atoms of Zn is 5.29 Kg
From Avogadro's hypothesis,
6.02×10²³ atoms = 1 mole of ZnRecall,
1 mole of Zn = 65.38 g
Converting 65.38 g to Kilogram (Kg), we have:
1000 g = 1 Kg
Therefore,
65.38 g = 65.38 / 1000
65.38 g = 0.06538 KgThus, we can say that,
6.02×10²³ atoms = 0.06538 Kg of ZnFinally, we shall determine the mass of Zn that contains 4.87×10²⁵ atoms. This can be obtained as follow:
6.02×10²³ atoms = 0.06538 Kg of Zn
4.87×10²⁵ atoms = [tex]\frac{4.87*10^{25} * 0.06538}{6.02*10^{23} } \\\\[/tex]
4.87×10²⁵ atoms = 5.29 Kg of ZnTherefore, the mass of 4.87×10²⁵ atoms of Zn is 5.29 Kg
Learn more: https://brainly.com/question/5809151
which of the following elements has the smallest atomic radius?
Answer:
helium is the smallest element and francium is the largest
Answer:
K+ is the right answer
Explanation:
A solution of transferrin was titrated with a standard solution of Fe3+. The blank absorbance was 0.04, and the absorbance of 10.00 mL of the transferrin solution measured after adding 6.00 mL of titrant was 0.65. Calculate the corrected absorbance that should be plotted.
Answer:
The correct answer is 0.61.
Explanation:
Based on the given information, a transferrin solution was titrated with a standard ferric solution. The blank absorbance was 0.04 and the absorbance of 10 ml solution of transferrin post supplementation of 6 ml titrant came out to be 0.65. The corrected optical density or absorbance can be determined by using the formula,
Corrected OD = Measured OD - Blank or Reference OD
Now putting the values we get,
Corrected OD = 0.65 - 0.04
Corrected OD = 0.61
Suppose that the microwave radiation has a wavelength of 12.4 cm . How many photons are required to heat 255 mL of coffee from 25.0 ∘C to 62.0 ∘C
Answer:
Explanation:
wavelength λ = 12.4 x 10⁻² m .
energy of one photon = h c / λ
= 6.6 x 10⁻³⁴ x 3 x 10⁸ / 12.4 x 10⁻²
= 1.6 x 10⁻²⁴ J .
Let density of coffee be equal to density of water .
mass of coffee = 255 x 1 = 255 g
heat required to heat up coffee = mass x specific heat x rise in temp
= 255 x 4.18 x ( 62-25 )
= 39438.3 J .
No of photons required = heat energy required / energy of one photon
= 39438.3 / 1.6 x 10⁻²⁴
= 24649 x 10²⁴
= 24.65 x 10²⁷ .
Bacteria reproduce by invading a host cell. *
Is it true or false
Answer:
i think its true but nevermind its true✌
In an enviroment in which the pH is 7, a carboxylic acid will exist as:
A) a negatively charged species
B)a positvely charged species
C)a neutral species
D)none of the other answers are correct
Answer:
The correct answer is C.
Explanation
The pH scale ranges from 0-14 so 7 is neutral.
which chemical equation is balanced
A: 2K+ H20. K20 + H2
B: MgO + 2HCI. MgCI2. + 2H2O
C: CO2 + H20. H2CO2
D: CaO2 +HCI. CaCI2 +H2O
Explanation:
right answer is A
2K + H20 → K20 + H2
Joints in train tracks are designed with extra space to allow for __________________ in hot weather.
Join in tracks are designed with extra space to allow for friction in hot weather
Answer:
Joints in train tracks are designed with extra space to allow for expansion and contraction of the track material in hot weather.
What do the flames below the pot
represent
Answer:
That it is cooking the food or whatever you have in the pot.
Explanation:
We are learning this in science.
Explain the difference in reactivity between CH3+OH2 and CH3OH in a nucleophilic substitution reaction.
Here ya go, hope this helps! :)
difference between elimination and substitution
Answer:
The obvious difference between substitution and elimination reactions is that substitution reactions replace one substituent with another while elimination reactions simply remove the substituent. ... The major difference between the groups is the number of steps the reaction takes place over.
substitution and elimination can be seenis by looking at the bond or the H+ . When substitution occurs, the H+ will be subtituted with other atom. As for elimination, when this reaction occur which mostly involve alkane, new bondwill appear.
Thank you and please rate me as brainliest as it will help me to level up
What is the mole ratio of oxygen to butane?
Answer:
13:2
With the number of moles of butane equal to 54 grams, it is possible to find the moles of O2 that can react with it. Taking coefficients from the reaction equation (13 O2 and 2 C4H10), the molar ratio of O2 to C4H10 is 13:2.
Explanation:
At higher temperatures, air can hold __vapor as compared to air at lower?
Answer:
water vapor
Explanation:
the the answer is water vapor
HELPP ANSWERSSS!!!!
A student designs an investigation to test the reactivity of two elements with HCl to produce hydrogen gas. Using the periodic table as a model which of the following would you expect to produce the most hydrogen gas within the first minute of the reaction?
A.
Al, because it has the higher ionization energy and more readily accepts electrons to participate in a reaction.
B.
Al, because it has the lower ionization energy and more readily gives up valence electrons to participate in a reaction.
C.
Cs, because it has the lower ionization energy and more easily gives up its valence electrons to participate in a reaction.
D.
Cs, because it has the higher ionization energy and more easily gives up its valence electrons to participate in a reaction.
Answer:
C. Cs, because it has the lower ionization energy and more easily gives up its valence electrons to participate in a reaction.
Explanation:
The Cs will produce the most hydrogen gas because it has a lower ionization energy and more easily gives up its valence electrons to participate in the reaction.
Ionization energy is the energy required to remove the most loosely held electrons in an atom. Atoms with lower ionization energy readily goes into reactions. This is because they will present little barrier for the reaction to occur.Which of these is purposefully changed during a scientific investigation?
Answer:
The independent variable is the variable that is deliberately changed by the scientist. The dependent variable is the one observed during the experiment. The dependent variable is the data we collect during the experiment.
Elements on the current periodic table are organized by what?
atomic number
number of neutron
reactivity
of rational function
1
3. + 3 < 0
3x-1
nctions.
Answer:
I didn't understand questions properly. Sorry
During a tug of war competition neither team was able to gain an advantage which of the following explains the force is this situation
A. The forces are balanced
B.the forces are overcome by air friction
C.the mass of the rope cancels is the forces being exerted on it
D.the forces are unbalanced
Answer:
b i did the test
Explanation:
how is the atmosphere characterized
which statement correctly describes the relationship between chlorine and argon?
Answer:
Argon has a larger atomic number and a larger atomic mass.
The transition metals are all group together on the periodic table all the following explains this grouping except?
A) They all have good conductivity
B) they are not found in nature as pure elements
C)they are used in construction and electrical applications
D) they are less reactive than elements in groups 1 and 2
How many g of a 5.0% by weight NaCl solution are needed to give 3.2 g NaCl?
Answer:
1.12
Explanation:
what are bonds in which valence electrons are shared
Answer:true
Explanation:
Covalent bonds are a class of chemical bonds where valence electrons are shared between two atoms, typically two nonmetals. The formation of a covalent bond allows the nonmetals to obey the octet rule and thus become more stable.
Answer:
covalent bonds are bonds in which valence electrons are shared.
Explanation:
Formula for cesium iodide
Answer:
Csl
Explanation:
Caesium iodide or cesium iodide is the ionic compound of caesium and iodine. It is often used as the input phosphor of an X-ray image intensifier tube found in fluoroscopy equipment. Caesium iodide photocathodes are highly efficient at extreme ultraviolet wavelengths.
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