Answer:
weight of H₂O formed = 2.3 grams H₂O (2 sig. figs.)
Explanation:
Rxn: CH₄(g) + 2O₂(g) => CO₂(g) + 2H₂O(g)
Given: 1.16g 4.16g 3.52g ? (g)
Moles: 1.16g/16g·mol⁻¹ 4.16g/32g·mol⁻¹ 3.52g/44g·mol⁻¹
= 0.0725mol. = 0.13mol. = 0.08mol. => ? (moles)
Limiting Reactant: Divide each mole value by related coefficient of balanced standard equation (that is, balanced with coefficients in lowest whole number ratios). The smaller value is the limiting reactant.
0.0725/1 0.13/2 0.080/1
= 0.0725 = 0.065 = 0.080
Limiting Reactant is O₂(g) => 0.065 is smaller value after dividing each mole value by related coefficient of balanced equation.
NOTE: When working problem, however, one must use the mole value calculated from given amount in grams. That is, in this case 0.13 mole O₂. The 'divide by related coefficient and check smaller value' is ONLY for identifying the limiting reactant. This trick works for ALL general chemistry problems.
Moles H₂O formed: Since the coefficient of the limiting reactant (O₂) equals the coefficient of water (H₂O), then the moles of water formed is 0.065 mole H₂O.
Weight (in grams) of H₂O formed:
Grams H₂O = moles H₂O x formula weight H₂O
= 0.13 mole H₂O x 18 g H₂O/mole H₂O
= 2.34 g H₂O (calculator answer)
= 2.3 g H₂O (final answer should be rounded to 2 sig. figs.) => form of final answer should be based on data in final computation having the least number of sig. figs.
Review: Sequence of calculations
Write and balance equation to smallest whole no. ratio of coefficients.If not in moles, convert given 'measured' data to dimension of moles. => moles = mass (g)/formula wt(g·mol⁻¹) => moles = volume of gas in Liters/Std Molar Volume (= 22.4L·mole⁻¹ at STP) => moles = no. of particles / Avogadro's No. (= 6.02 x 10²³ part's/mole)Determine Limiting Reactant => mole values of each compound given / related coefficient in standard equation => smallest value is L.R.Determine moles of unknown needed/used/formed from limiting reactant in moles and coefficient of unknown compound in standard equation given data values.=> moles of limiting reactant / coefficient of same cpd. in std. equation = unknown (X) / coefficient of same (unknown) cpd. in std. equation
=> cross multiply and solve for unknown (X)
=> L.R.(moles) / eqn. coef. of L.R. = X / eqn. coef. of X
=> (L.R.(calc'd moles)(eqn. coef. of X) = (X)(eqn. coef. of L.R.)
=> X (in moles) = (L.R.(calc'd. moles)(eqn. coef. of X) / (eqn. coef. of L.R.)
Convert X-answer in moles to desired dimension specified in problem.=> grams = moles x formula wt.
=> volume (L) = moles x std. volume (= 22.4L/mole)
=> #particles = moles x Avogadro's Number (= 6.02 x 10²³ parts/mole)
Calculate the amount of heat energy is needed to raise the temperature of 5.00 grams of lead from 25.0 to 35.0 degrees Celsius, if the specific heat capacity of lead is 0.129 J/g/C.
Answer: 6.45 Joules
Explanation: I just did it
Which of the following relationships is true?
A. pH − pOH = 14
B. Ka × Kb = 1 × 10-14
C. pKa × pKb = 14
D. pKa × pKb = 1 × 10-14
Answer:
D. pKa × pKb = 1 × 10-14
Explanation:
hope this helps, if not, give me time to edit
Answer:
B. Ka × Kb = 1 × 10-14
Explanation:
yw
solute separates as a solid when a saturated solution is cooled why
Answer:
When a saturated solution at a high temperature is cooled, why is the solution separated as a solid? When a saturated solution at a high temperature is cooled, inter molecular space between the molecules of the solution decreases. As a result, no more solute can remain in a solution separating out as a solid crystal.
How many moles are in 25.0 grams of KMnO4?
0.124 mol KMnO4
0.158 mol KMnO4
0.199 mol KMnO4
0.316 mol KMnO4
Answer:
158 mol :)
Explanation:
HELP ASAP
Which of these atoms ihas the HIGHEST reactivity?
Answer:
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What is the elevation of point x on rock mountain ( Ik it's blury but please help for 30 points ) ty
Explanation:
A contour map shows two locations, X and Y, 5 kilometers apart. The elevation at location X is 800 meters and the elevation at location Y is 600 meters.
how many moles are 2.54 x 10^29 molecues of H2O
Answer:
[tex]\boxed {\boxed {\sf 421,786.7818 \ mol \ H_2O}}[/tex]
Explanation:
We are asked to convert from molecules of water to moles.
1. Avogadro's Number1 mole of any substance contains the same number of particles (atoms, molecules, formula units, etc). This is Avogadro's Number: 6.022*10²³. In this problem, the particles are molecules of water.
2. Convert Molecules to MolesUse Avogadro's Number to make a ratio.
[tex]\frac {6.022 *10^{23} \ molecules \ H_2O}{1 \ mol \ H_2O}[/tex]
Multiply by the number of molecules given: 2.54 *10²⁹
[tex]2.54 *10^{29} \ molecules \ H_2O \times \frac {6.022 *10^{23} \ molecules \ H_2O}{1 \ mol \ H_2O}[/tex]
Flip the ratio so the units of molecules of water cancel.
[tex]2.54 *10^{29} \ molecules \ H_2O \times \frac {1 \ mol \ H_2O}{6.022 *10^{23} \ molecules \ H_2O}[/tex]
[tex]2.54 *10^{29} \times \frac {1 \ mol \ H_2O}{6.022 *10^{23} }[/tex]
Condense the problem into 1 fraction.
[tex]\frac {2.54 *10^{29} }{6.022 *10^{23} }\ mol \ H_2O[/tex]
[tex]421786.7818 \ mol \ H_2O[/tex]
2.54 *10²⁹ molecules of water are 421, 786.7818 moles of water.
3.) If you have 784 g of Sulfuric Acid (H2SO4), how many moles of Sulfuric
Acid is that? *
Answer:
98.07848
Explanation:
I assume you are converting between grams H2SO4 and mole. You can view more details on each measurement unit: molecular weight of H2SO4 or mol This compound is also known as Sulfuric Acid. The SI base unit for amount of substance is the mole.
Answer:
8moles
Explanation:
n=m/GFM
n=784/98.02
n=7.998
n=8moles
If an object is on top of a hill or in a position raised above the ground, it must have __________.
Answer:
The force applied to the object is an external force, from outside the system. When it does positive work it increases the gravitational potential energy of the system. Because gravitational potential energy depends on relative position, we need a reference level at which to set the potential energy equal to 0.
If an object is on top of a hill or in a position raised above the ground, it must have gravitational potential energy.
What is Potential Energy ?
In physics, potential energy is the energy held by an object because of its position relative to other objects, stresses within itself, its electric charge, or other factors
If an object is lifted, work is done against the force of gravity.
When work is done energy is transferred to the object and it gains gravitational potential energy.
If the object falls from that height, the same amount of work would have to be done by the force of gravity to bring it back to the Earth’s surface.
Due to the Principle of Conservation of Energy we can say that:
Gravitational potential energy at the top = kinetic energy at the bottom
To know more about Potential Energy
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Describe how you could show that a compound is an acid
How much energy is released when 75g of liquid water is reduced from 65c to 0c and completely freezes?
Answer:
Q = 20377.5 Joules
Explanation:
Given the following data;
Mass = 75g
Initial temperature = 65°C
Final temperature = 0°C
Specific heat capacity of water = 4.18 J/g°C.
To find the quantity of heat released;
Heat capacity is given by the formula;
[tex] Q = mcdt[/tex]
Where;
Q represents the heat capacity or quantity of heat.
m represents the mass of an object.
c represents the specific heat capacity of water.
dt represents the change in temperature.
Substituting into the equation, we have;
[tex] Q = 75 * 4.18 * 65 [/tex]
Q = 20377.5 Joules
how to calculate the mass percent of hydrogen
Answer:
divide the mass of element in 1 mole of the compound by the compound's molar mass and multiply the answer by 100.
Explanation:
take the molar mass of hydrogen in the water molecule, divide by the total molar mass of water, and multiply by 100.
does it help?
What happens when a current is applied to two electrodes immersed in pure water?
A. No electrolysis occurs, and current does not flow.
B. Oxygen, but not hydrogen, is released as a gas.
C. Electrolysis occurs, releasing oxygen and hydrogen gas.
Answer:
b
Explanation:
Gucci ghhvhjhsgjjn hvh
Answer:
B
Explanation:
Look at the diagram below. According to the diagram, what substance(s) are the
reactant(s)? What substance(s) are the product(s)? Explain your reasoning.
NH3(aq) + HCI (aa)
Ammonia Hydrochloric acid
NHCI (aa)
Ammonium chloride
You will be graded on the following rubric:
luje
Answer:
NH3(aq) and HCl(aq) are the reactants, while NH4Cl(aq) is the product.
Explanation:
The hydrogen atom from the HCl molecule joins the other three in NH3 creating a four hydrogen molecule, NH4Cl.
I need help everyone
Answer:
The answer is D
The last one
how are fossils discovered
Which of the following is NOT a type of mucle tissue?
Cardiac
Smooth
Striped
Skeletal
Answer:
Striped should be the answer
A neutral atom has a ground state electron configuration of 1s22s22p63s2.The neutral atom becomes an ion during a chemical reaction.Which is the most likely charge of the ion
Answer:
+2
Explanation:
the atom will acquire the noble gas configuration if it loses 2 electrons, becoming a divalent cation
Can someone pleasee help me with this asap!! Im struggling
4a. D - The last number in the configuration represents the group, in this case 3, and the number of shells represent the period, which is also 3.
4bi. Rubidium metal reacts very rapidly with water to form a colourless solution of rubidium hydroxide (RbOH) and hydrogen gas (H2). The resulting solution is basic because of the dissolved hydroxide. The reaction is very exothermic and explosive.
4bii. Lithium is smaller in size than potassium . so valence electrons are more tightly held in Li than K. Due to larger size of K the valence electrons are loosely held and easy to remove the electron from K. Hence K is more reactive.
What must happen to uranium before it can be used as a fuel source?
A. No changes are necessary.
B. Stable U-235 must be enriched with 3% radioactive U-238.
C. Stable U-238 must be enriched with 3% radioactive U-235.
D. Unstable U-235 must be enriched with 5% U-238 to stabilize it.
Answer:
D
Explanation:
Before it can be used in a reactor for electricity generation, however, it must undergo a series of processes to produce a useable fuel. For most of the world's reactors, the next step in making the fuel is to convert the uranium oxide into a gas, uranium hexafluoride (UF6), which enables it to be enriched.
Unstable U-235 must be enriched with 5% U-238 to stabilize it. Hence, option D is correct.
What is radioactive?Radioactivity is the phenomenon of the spontaneous disintegration of unstable atomic nuclei into atomic nuclei to form more energetically stable atomic nuclei.
Before uranium can be used in a reactor for electricity generation, however, it must undergo a series of processes to produce a useable fuel.
For most of the world's reactors, the next step in making the fuel is to convert the uranium oxide into a gas, uranium hexafluoride (UF6), which enables it to be enriched.
Hence, option D is correct.
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Hurry please need fast
In the following chemical phrase how many moles of O are there? 6
C2H602* 2
6
12
3
.What is the significance of genetic variation within the population of moths during and after the Industrial Revolution in London?
Answer:
The evolution of the peppered moth is an evolutionary instance of directional colour change in the moth. The frequency of dark-coloured moths increased at that time, an example of industrial melanism.
Explanation:
I did this on Savvas Realize got it right.
Genetic variation is said to be the difference in the hereditary sequence. After the industrial revolution, the frequency of the dark-colored moth increased dramatically more than the light-colored moths.
What is industrial melanism?
Industrial melanism was an example of the evolutionary effect that occurred in the moths where the dark-colored species were favored over the light-colored species of peppered moths.
Before the industrial population, light-colored moths were large in number which later decreased with an increase in pollution. This occurred due to an increase in the pollutants and dust deposition that altered the environment.
As the pollution increased over time the dark-colored moths became dominant and increased their population over time. This is an example of industrial melanism as the color of the body was the determining factor in survival.
Therefore, dark-colored moths were prevalent after the industrial revolution.
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Which is not an example of a
parasite/host relationship?
A flea on a dog
A tick on a horse
A toad on a lily pad
A barnacle on a whale
Answer:
A toad on lily pad
Explanation:
have a great day
What is the amount of space that a material takes up ?
volume.
The amount of space a material occupies is its volume.
Mass is measured using a scale. Volume is the amount of space matter takes up. Volume can be measured by multiplying the length, width, and height of an object, or by using a measuring cup and seeing how the measurement of water changes in a cup. Density is the amount of matter an object has in a certain space.
Answer:
Volume
Explanation:
Mass is measured using a scale. Volume is the amount of space matter takes up. Volume can be measured by multiplying the length, width, and height of an object, or by using a measuring cup and seeing how the measurement of water changes in a cup. Density is the amount of matter an object has in a certain space.
PLEASE HELP ME ASAP!!! 10 POINTS!!
The three equations below represent nuclear fission and nuclear fusion reactions. For each equation, tell whether fission or fusion has occurred and write the missing term in the equation.
A) ²³⁵₉₂ U+n→⁹⁵₃₈Sr+____+2n
B) ³₁H+²₁H→⁴₂H+____
C) ____+n→⁹²₃₉Y+¹⁴⁰₅₃I+2n
Explanation:
A) fission: Iodine-140 (atomic number = 53)
B) fusion: 1 neutron
C) fission: Uranium-233 (atomic number = 92)
Plz Answer this if you Answer this right you will get brainliest
Don't Answer this question if you don't know you will be reported
Reaction 1 :-
AlZn²⁺Zn²⁺AlReaction 2 :-
LiAl³⁺Al³⁺Li____________________In order to calculate the number of neutrons you must subtract the what from the what?
Answer:
You take the atomic, or proton number of the element, and you subtract it from the element's mass number.
Answer:
protons
Explanation:
neutrons and protons make up the mass of the atom
Which of the following is a method for measuring energy in food?
A. reading the label
B. filtration
C. chromatography
D. calorimetry
Hii! i’m timed so can someone please answer quickly!
What is the frequency of this wave? 1,2,3, or 4
I cant find any answers to this question! i really appreciate it!
Count the in between joint bunches of curve lines .
First one at beginninglast one at end .And one is in middleFrequency is 3-1=2
Which statement about noble gases is correct? *
They are extremely rare in nature.
They are highly reactive with both metals and nonmetals.
O They exist as single atoms rather than as molecules.
O They form compounds with very bright colors.
Answer:
Hello There!!
Explanation:
I believe the answer is O They form compounds with very bright colors.
hope this helps,have a great day!!
~Pinky~
The statement about noble gases that is correct is D. They form compounds with very bright colors.
Noble gases simply refers to the elements that have similar properties. Noble gases are colorless, odorless, and have very low reactivity.
Examples of noble gases are helium, argon, Krypton, xenon, etc. Noble gases also form compounds with very bright colors.
In conclusion, the correct option is D.
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