Answer:
[tex]\Delta _rH=-39,1kJ[/tex]
Explanation:
Hello!
In this case, since it is possible to assume that the heat released by the reaction is absorbed by the water in the calorimeter we can write:
[tex]Q_{rxn}=-200mL*\frac{1g}{1mL}*4.184\frac{J}{g\°C}*(23.20\°C-21.80\°C)\\\\Q_{rxn}=-1,171.5J[/tex]
Now, since the reaction between silver nitrate and hydrochloric acid is:
[tex]HCl+AgNO_3\rightarrow AgCl+HNO_3[/tex]
We can see there is a reacting 1:1 mole ratio, thus, the reacting moles are computed via the molarity of the solutions:
[tex]n=0.300mol/L*0.100L=0.0300mol[/tex]
Finally, the enthalpy of reaction is:
[tex]\Delta _rH=\frac{-1,171.5J}{0.0300mol}=-39,050.7J[/tex]
And in kJ:
[tex]\Delta _rH=-39,1kJ[/tex]
Best regards!
I just need my answers checked please be quick
Answer:
they are all right
Explanation:
What is the mass in grams of 1.00 x 10^12 lead (Pb)
atoms?
3.44 × 10⁻¹⁰ g Pb
General Formulas and Concepts:Math
Pre-Algebra
Order of Operations: BPEMDAS
Brackets Parenthesis Exponents Multiplication Division Addition Subtraction Left to RightChemistry
Atomic Structure
Reading a Periodic TableAvogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.Stoichiometry
Using Dimensional AnalysisExplanation:Step 1: Define
[Given] 1.00 × 10¹² atoms Pb
[Solve] grams Pb
Step 2: Identify Conversions
Avogadro's Number
[PT] Molar Mass of Pb - 207.2 g/mol
Step 3: Convert
[DA] Set up: [tex]\displaystyle 1.00 \cdot 10^{12} \ atoms \ Pb(\frac{1 \ mol \ Pb}{6.022 \cdot 10^{23} \ atoms \ Pb})(\frac{207.2 \ g \ Pb}{1 \ mol \ Pb})[/tex][DA] Multiply/Divide [Cancel out units]: [tex]\displaystyle 3.44072 \cdot 10^{-10} \ g \ Pb[/tex]Step 4: Check
Follow sig fig rules and round. We are given 3 sig figs.
3.44072 × 10⁻¹⁰ g Pb ≈ 3.44 × 10⁻¹⁰ g Pb
Answer:
[tex]\boxed {\boxed {\sf 3.44 *10^{-10} \ g \ Pb}}[/tex]
Explanation:
1. Atoms to Moles
Use Avogadro's Number to convert atoms to moles. This number: 6.022*10²³, tells us the number of particles (atoms, molecules, etc.) in 1 mole of a substance. In this case, the particles are atoms of lead.
[tex]\frac {6.022*10^{23} \ atoms \ Pb}{1 \ mol \ Pb}[/tex]
Multiply by the given number of atoms.
[tex]1.00 *10^{12} \ atoms \ Pb *\frac {6.022*10^{23} \ atoms \ Pb}{1 \ mol \ Pb}[/tex]
Flip the fraction so the atoms of lead cancel.
[tex]1.00 *10^{12} \ atoms \ Pb *\frac {1 \ mol \ Pb}{6.022*10^{23} \ atoms \ Pb}[/tex]
[tex]1.00 *10^{12}*\frac {1 \ mol \ Pb}{6.022*10^{23}}[/tex]
[tex]\frac {1.00 *10^{12}\ mol \ Pb}{6.022*10^{23}} = 1.66057788*10^{-12} \ mol \ Pb[/tex]
2. Moles to Grams
Use the molar mass to convert moles to grams. This can be found on the Periodic Table. For lead it is 207.2 grams per mole.
[tex]\frac {207.2 \ g\ Pb}{ 1 \ mol \ Pb}[/tex]
Multiply by the number of moles we calculated.
[tex]1.66057788*10^{-12} \ mol \ Pb* \frac {207.2 \ g\ Pb}{ 1 \ mol \ Pb}[/tex]
[tex]1.66057788*10^{-12}* \frac {207.2 \ g\ Pb}{ 1 }[/tex]
[tex]1.66057788*10^{-12}* {207.2 \ g\ Pb}= 3.44071737*10^{-10} \ g \ Pb[/tex]
3. Round
The original measurement of atoms has 3 significant figures, so our answer must have the same. For the number we calculated, it is the hundredth place. The 0 in the thousandth place tells us to leave the 4.
[tex]3.44 *10^{-10} \ g \ Pb[/tex]
Which of the following a true statement about igneous rocks?
A: Igneous rocks are only formed under a lot of heat and pressure. Some igneous rocks are formed below the surface others in oceans.
B: The properties of igneous rocks depend on the location in which they are formed.
C: Wind and water erosion can create igneous rocks.
Answer:
i think the answer is A....
Explanation:
Igneous rocks (from the Latin word for fire) form when hot, molten rock crystallizes and solidifies. The melt originates deep within the Earth near active plate boundaries or hot spots, then rises toward the surface.
Given the decomposition of hydrogen peroxide, calculate the moles of oxygen gas produced from 4.20 mol of H2O2.
2H2O2(l)→2H2O(l)+O2(g)
Answer:
2.10 moles of O₂
Explanation:
2 H₂O₂ (l) → 2H₂O(l) + O₂(g)
In this reaction we say, that 2 moles of hydrogen peroxide can decompose to 2 moles of water and 1 mol of oyxgen.
So ratio is 2:1, according to stoichiometry.
If we apply a rule of three;
2 moles of hydrogen peroxide can decompose to 1 mol of oxygen
Then 4.20 moles of hydrogen peroxide may produced (4.20 . 1)/2 =
2.10 moles of O₂
3. Calculate the energy in joules) of a photon with a wavelength of 3.66 X 104 hm (Infrared region) (Hint: Use Planck's equation)
104.3 x 10")
104.3 x 10-21,
1.043 X 1033
5.43 x 10 21
Answer:
5.43×10¯³² J
Explanation:
From the question given above, the following data were obtained:
Wavelength (λ) = 3.66×10⁴ hm
Energy (E) =?
Next, we shall convert 3.66×10⁴ hm to metre (m). This can be obtained as follow:
1 hm = 100 m
Therefore,
3.66×10⁴ hm = 3.66×10⁴ hm × 100 m / 1 hm
3.66×10⁴ hm = 3.66×10⁶ m
Next, we shall determine the frequency of the frequency of the photon. This can be obtained as follow:
Wavelength (λ) = 3.66×10⁶ m
Velocity (v) = 3×10⁸ m/s
Frequency (f) =?
v = λf
3×10⁸ = 3.66×10⁶ × f
Divide both side by 3.66×10⁶
f = 3×10⁸ / 3.66×10⁶
f = 81.97 Hz
Finally, we shall determine the energy of the photon. This can be obtained as follow:
Frequency (f) = 81.97 Hz
Planck's constant (h) = 6.63×10¯³⁴ Js
Energy (E) =?
E = hf
E = 6.63×10¯³⁴ × 81.97
E = 5.43×10¯³² J
Therefore, the energy of the photon is 5.43×10¯³² J
How many moles of F are in 8.25 grams of F?
0.434 mol F
General Formulas and Concepts:Math
Pre-Algebra
Order of Operations: BPEMDAS
Brackets Parenthesis Exponents Multiplication Division Addition Subtraction Left to RightChemistry
Atomic Structure
Reading a Periodic TablesMolesStoichiometry
Using Dimensional AnalysisExplanation:Step 1: Define
[Given] 8.25 g F
[Solve] moles F
Step 2: Identify Conversions
[PT] Molar Mass of F - 19.00 g/mol
Step 3: Convert
[DA] Set up: [tex]\displaystyle 8.25 \ g \ F(\frac{1 \ mol \ F}{19.00 \ g \ F})[/tex][DA] Multiply [Cancel out units]: [tex]\displaystyle 0.434211 \ mol \ F[/tex]Step 4: Check
Follow sig fig rules and round. We are given 3 sig figs.
0.434211 mol F ≈ 0.434 mol F
When gases are treated as real, via use of the van der Waals equation, the actual volume occupied by gas molecules ________ the pressure exerted and the attractive forces between gas molecules ________ the pressure exerted, as compared to an ideal gas.
decreases, increases
does not affect, decreases
increases, decreases
does not affect, increases
increases, increases
Answer:
Increases, decreases
Explanation:
What number will go in the _?_ below to balance the equation?
3Gr3V2 + O3 --> 3GrO + __?__V
Question 1 options:
A. 1
B. 2
C. 3
D. 4
E. 5
F. 6
G. 9
Answer:
Option F 6 will be the answer.
What is occurring with the velocity between points D and E?
A velocity is decreasing
B. velocity is increasing
C. velocity is constant
D. velocity is zero
Answer:
a
Explanation:
the line is going down
To determine the highest angle the pendulum will swing to after the impact, we can apply the principle of conservation of momentum. Initially, the total momentum is zero since the pendulum is at rest.
After the impact, the total momentum remains zero because the block and embedded projectile move together as a single system.First, let's convert the weight units to a common system. The 5-pound rod is approximately 2.27 kg, and the 10-pound wooden block is around 4.54 kg. The projectile's weight is 0.3 oz, which is about 0.0085 kg.The momentum before the impact is zero, so the momentum after the impact must also be zero. This can be expressed as:(2.27 kg + 4.54 kg + 0.0085 kg) * V_final = 0Solving for V_final gives us V_final ≈ 0 ft/s. Since the velocity is zero after the impact, the pendulum will momentarily stop at its highest point.Therefore, the highest angle the pendulum will swing to after the impact is 0 degrees, or it will come to rest at the vertical position.
Learn more about momentum here :
https://brainly.com/question/30677308
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You dissolve 0.47 g of potassium chloride (KCl) in 700 ml of water.
What is the molarity of the solution?
(From the periodic table: 1 mol K = 39.10 g; 1 mol Cl = 35.453 g)
Enter the value rounded to three decimal places with no units
Will give BRAINLEst
Answer:
0.009
Explanation:
Molarity, a measure of molar concentration of a substance is calculated thus;
Molarity = number of moles ÷ volume
According to the provided information, mass of KCl = 0.47g, volume of water = 700ml
Using mole = mass/molar mass
Molar Mass of KCl = 39.10 + 35.453
= 74.553g/mol
Mole = 0.47/74.55
Mole = 0.0063mol
Volume of water = 700ml = 700/1000 = 0.7L
Molarity = 0.006/0.7
Molarity = 0.00857
The value of molarity rounded to three decimal places (3 d.p) = 0.009
(55 points) Please help me with my homework please please help me thanks so much
Explanation:
the most important observations is the conversion of electrical energy into light energy which performs the function of a lamp
in addition to this there is considerable amount of energy loss in form of heat energy when the electrical lamp is there is production of a result of this is not converted into light energy
Choose all the answers that apply.
Which of the following increases erosion?
careless farming
crop rotation
leaving fields unplanted
clearing forests
contour plowing
Answer:
1, 3, and 5
Further Information:
Careless farming - increases erosion
Crop rotation - does not increase erosion
Leaving fields unplanted- increases erosion
Clearing forests - does not increase erosion
Contour plowing - increases erosion
Hope this helps and brainliest would be greatly appreciated!!
Benzoic acid is a white crystalline powder used as a food preservative the compound contains 68.8% carbon, 5.0% hydrogen and 26.2% oxygen by mass what is the empirical formula
Weather is caused by the:
mesosphere
stratosphere
troposphere
thermosphere
I WILL MARK BRAINLIST
_Na+ Cl2 - -> _NaCl
A 2,4
B 1,2
C 3,3
D 2,2
Answer:
D 2,2
Explanation:
We can see that there are 2 chlorines on the reactant side so there has to be a 2 on the product side
Now we have Na + Cl2 --> 2NaCl
The problem now is that there are 2 sodiums on the product side so add a 2 to the Na on the reactant side
2Na + Cl2 --> 2NaCl
Now it's balanced!
The density of ethanol, C2H5OH, is 0.789 g/mL. How many milliliters of ethanol are needed to produce 18.2 g of CO2 according to the following chemical equation?
C2H5OH(l) + 3 O2(g) → 2 CO2(g) + 3 H2O(l)
Answer: 12.1 ml of ethanol is needed
Explanation:
To calculate the moles :
[tex]\text{Moles of solute}=\frac{\text{given mass}}{\text{Molar Mass}}[/tex]
[tex]\text{Moles of} CO_2=\frac{18.2g}{44g/mol}=0.414moles[/tex]
[tex]C_2H_5OH(l)+3O_2(g)\rightarrow 2CO_2(g)+3H_2O(l)[/tex]
According to stoichiometry :
2 moles of [tex]CO_2[/tex] is produced by = 1 mole of [tex]C_2H_5OH[/tex]
Thus 0.414 moles of [tex]CO_2[/tex] is produced by=[tex]\frac{1}{2}\times 0.414=0.207moles[/tex] of [tex]C_2H_5OH[/tex]
Mass of [tex]C_2H_5OH=moles\times {\text {Molar mass}}=0.207moles\times 46.07g/mol=9.54g[/tex]
Volume of ethanol = [tex]\frac{\text {Mass of ethanol}}{\text {density of ethanol}}=\frac{9.54g}{0.789g/ml}=12.1ml[/tex]
12.1 ml of ethanol is needed to produce 18.2 g of [tex]CO_2[/tex]
2NH3(g) <--> N2(g)+3H2(g)
Which is most likely the effect to the forward reaction if there is an increase in pressure of the system?
The reactant surface area increases.
The reaction rate decreases.
The reaction is not affected at all.
The reaction stops completely.
Answer:
B. The reaction rate decreases.
Explanation:
Consider the following reaction:
Fe3+(aq) + SCN-(aq) ↔︎ [Fe(SCN)]2-(aq)
1)Explain what is meant by the term dynamic equilibrium.
2) Write the equilibrium expression for the reaction.
3) The numerical value of Kc at 298K is about 1000 for the reaction. What does this tell you about the position of the equilibrium at 298K?
Answer: In 1860s, Norwegian scientists C. M. Guldberg and P. Waage noted a peculiar relationship between the amounts of reactants and products in an equilibrium. Today, we call this observation the law of mass action. It relates the amounts of reactants and products at equilibrium for a chemical reaction. For a general chemical reaction occurring in solution, aA + bB ⇄ cC + dD the equilibrium constant, also known as Keq, is defined by the following expression: Keq = [C]c/[D]d where [A] is the molar concentration of species A at equilibrium, and so forth. The coefficients a, b, c, and d in the chemical equation become exponents in the expression for Keq. The Keq is a characteristic numerical value for a given reaction at a given temperature. That is, each chemical reaction has its own characteristic Keq. The concentration of each reactant and product in a chemical reaction at equilibrium is related; the concentrations cannot be random values, but they depend on each other. The numerator of the expression for Keq has the concentrations of every product (however many products there are), while the denominator of the expression for Keq has the concentrations of every reactant, leading to the common products over reactants definition for the Keq. Let us consider a simple example. Suppose we have this equilibrium: A ⇄ B .There is one reactant, one product, and the coefficients on each are just 1. The Keq expression for this equilibrium is Keq = [B]/[A]. Exponents of 1 on each concentration are understood. Suppose the numerical value of Keq for this chemical reaction is 2.0. If [B] = 4.0 M, then [A] must equal 2.0 M so that the value of the fraction equals 2.0: Keq = [B]/[A] = 4.0/2.0 =2.0 .By convention, the units are understood to be M and are omitted from the Keq expression. Suppose [B] were 6.0 M. For the Keq value to remain constant (it is, after all, called the equilibrium constant), then [A] would have to be 3.0 M at equilibrium: Keq = [B]/[A] = 60/3.0= 2.0 .If [A] were not equal to 3.0 M, the reaction would not be at equilibrium, and a net reaction would occur until that ratio was indeed 2.0. At that point, the reaction is at equilibrium, and any net change would cease. However, that the forward and reverse reactions do not stop because chemical equilibrium is dynamic.
Chemical formula of copper (II) nitrate
Give the theoretical yield, in moles, of CO2 from the reaction of 1.45 moles of C8H18 with 1.45 moles of O2.
2 C8H18 + 25 O2 → 16 CO2 + 18 H2O
Answer:
vuvbuvivovoivuighhghgig
How many grams are in 7.32 x 1023 molecules of potassium carbonate (K2CO3)?
(I leave off the x10^23 because they both will divide out) Use your per
what is organic chemistry?
Answer:
Organic chemistry is the scientific study of the structure, properties, compositions, reactions and synthesis of organic compounds that by definition contains carbon.The organic compounds are molecules composed of carbon and hydrogen and it may contain any number of other elements.
Maybe this was your answer for your question.
Which yield comes from measurements obtained during a real experiment?
A) actual yield
B) theoretical yield
C) percent yield
Answer:
A) actual yield
Explanation:
Theoretical yield is the amount of product expected based on the stoichiomety.
Percent yield is the actual yield over the theoretical yield.
Which of the following do omnivores eat?
A. only
B. plants and meat
C. meat only
D. they make their own food
Answer:
(B. Plants and meat)
Explanation:
Post-Lecture Assignment Chapter 06
Animation-Changes of State
< 1 of 23 >
When a solid is placed in a container and heat is applied, a phase change occurs. Watch the video and sort the parts of the curve based on whether the average energy of the molecules is changing, or is constant.
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The liquid is heated at the boiling point
The solid is heated at the melting
point
The liquid is heated to reach the
boiling point
The solid is heated to reach the
melting point
Average molecule energy change
Average molecule energy constant
Submit
Answer:
Can you send an image of the question, please?
Explanation:
When magnesium reacts with oxygen, magnesium atoms lose electrons.
What happens to magnesium in this reaction?
A. It is reduced.
B. It is oxidized.
C. It is decomposed.
D. It undergoes redox.
Answer:
B : it is oxidized .
Explanation:
During which changes of state do atoms that connot move past one another becomes free to move?
a. Vaporization and sublimation
b. boiling and deposition
c. sublimation and melting
d. condensation and melting
Answer:
c. sublimation and melting
Hope it helps...
Have a great day : )
Answer:
Option C is your answer
C. sublimation and melting
Explanation:
hope it helps u ^_^
have a great day/night
Name 2 diatomic molecules.
Which of the following statements about maintaining a fitness program is ture?
Answer:
im sorry but you havent posted the pic
Explanation:
Given the following chemical reaction equation:
3 Mg (s) + Al2O3 (s)------> 3 MgO (s) + 2 Al (s)
and 144g of MG and 150g of Al2O3 are reacted.
which chemical compound is the limiting reactant compound?
Answer:
Al₂O₃ is the limiting reactant
Explanation:
The limiting reagent or limiting reactant in a chemical reaction is a reactant that is totally used up when the chemical reaction is completed and subsequently, the reaction stops as no more products can be formed from the excess reactant.
Equation of the the reaction reaction is given below:
3 Mg (s) + Al₂O₃ (s) ----> 3 MgO (s) + 2 Al (s)
Mole ratio of reactants from the equation shows that 3 moles of magnesium metal is required to react with 1 mole of aluminum oxide.
Molar mass of magnesium metal, Mg = 24 g/mol
Molar mass of aluminum oxide, Al₂O₃ = (27 * 2 + 16 * 3) = 102 g/mol
from the equation of reaction, (24 * 3 g) 72 g of Mg reacts with 102 g of Al₂O₃
Given masses of reactants:
144 g of Mg = 144/24 6 moles of Mg
150 g of Al₂O₃ = 1.47 moles of Al₂O₃
Mole ratio of Mg to Al₂O₃ = 6/1.47 = 4.08 : 1
Therefore, magnesium is excess reactant while Al₂O₃ is the limiting reactant