Answer and Explanation:
Yes. The determination of melting point is used to analyze if a solid compound is pure or impure. The melting point of a pure solid product does not vary in a narrow range, whereas if impurities are present the solid melts in a broad range of temperatures. For this reason, this technique is generally used to determine the identity and purity of the products obtained in chemical reactions.
The energy stored in an object is called potential energy
True or false
its true
Potential energy is the stored or latent energy in an object at rest. It’s fundamental to many physics-related concepts because its laws hold true on any level, from the planetary to the atomic level. The potential energy of an object is measurable.
When of a certain molecular compound X are dissolved in of benzene , the freezing point of the solution is measured to be . Calculate the molar mass of X. If you need any additional information on benzene, use only what you find in the ALEKS Data resource. Also, be sure your answer has a unit symbol, and is rounded to the correct number of significant digits.
The question is incomplete. Here is the complete question.
When 2.10 g of a certain molecular compound X are dissolved in 65.0 g of benzene (C₆H₆), the freezing point of the solution is measured to be 3.5°C. Calculate the molar mass of X. If you need any additional information on benzene, use only what you find in the ALEKS Data resource. Also, be sure your answer has a unit symbol, and is rounded to 2 significant digits.
Answer: MM = 47.30 g/mol.
Explanation: There is a relationship between freezing point depression and molality. With this last one, is possible to calculate molar mass or molar weight of a compound.
Freezing Point Depression occurs when a solute is added to a solvent: the freezing point of the solvent decreases when a non-volatile solute is incremented.
Molality or molal concentration is a quantity of solute dissolved in a certain mass, in kg, of solvent. Its symbol is m and it's defined as
[tex]m=\frac{moles(solute)}{kg(solvent)}[/tex]
Freezing point depression and molal are related as the following:
[tex]\Delta T_{f}=K_{f}.m[/tex]
where
[tex]\Delta T_{f}[/tex] is freezing point depression of solution
[tex]K_{f}[/tex] is molal freezing point depression constant
m is molality
Now, to determine molar mass, first, find molality of the mixture:
[tex]\Delta T_{f}=K_{f}.m[/tex]
[tex]m=\frac{\Delta T_{f}}{K_{f}}[/tex]
For benzene, constant is 5.12°C/molal. Then
[tex]m=\frac{3.5}{5.12}[/tex]
m = 0.683 molal
Second, knowing the relationship between molal and moles of solute, determine the last one:
[tex]m=\frac{moles(solute)}{kg(solvent)}[/tex]
[tex]mol(solute)=m.kg(solvent)[/tex]
mol(solute) = 0.683(0.065)
mol(solute) = 0.044 mol
The definition for Molar mass is the mass in grams of 1 mol of substance:
[tex]n(moles)=\frac{m(g)}{MM(g/mol)}[/tex]
[tex]MM=\frac{m}{n}[/tex]
In the mixture, there are 0.044 moles of X, so its molecular mass is
[tex]MM=\frac{2.1}{0.044}[/tex]
MM = 47.30 g/mol
The molecular compound X has molecular mass of 47.30 g/mol.
Ivy has a mixture salt and sand . She wants to separate the two substances by pouring the mixture into a jar of water . How could ivy speed up the separation of the two substance? Shake the jar , put the jar into the freezer, add a third substance such as soil to the jar , remove some of the water from the jar before adding the mixture
Answer:
Remove some water from the jar before adding the mixture.
Explanation:
She will speed it up when removing some water it will stay dry and not be sticky to separate the two ingredients
Answer: Remove a bit of water from the jar
Explanation:
In the United States, barometric pressures a re generally reported in inches of mercury (in. Hg). On a beautiful summer day in Chicago, the barometric pressure is 30.45 in. Hg. Convert this pressure to torr.
Answer:
773.43 torr
Explanation:
From the question given above, the following data were obtained:
Pressure (in inHg) = 30.45 inHg
Pressure (in torr) =?
We can convert 30.45 inHg to torr by doing the following:
1 inHg = 25.4 torr
Therefore,
30.45 inHg = 30.45 inHg × 25.4 torr / 1 inHg
30.45 inhg = 773.43 torr
Thus, 30.45 inhg is equivalent to 773.43 torr
4) 568 cm3 of chlorine at 25° C will occupy 400 cm3 at what temperature given a constant pressure?
The final temperature : T₂=209.86 K = -63.1 °C
Further explanationGiven
V₁=568 cm³
T₁=25° C+ 273 = 298 K
V₂=400 cm³
Required
Final temperature(T2)
Solution
Charles's Law
When the gas pressure is kept constant, the gas volume is proportional to the temperature
[tex]\tt \dfrac{V_1}{T_1}=\dfrac{V_2}{T_2}[/tex]
T₂=(V₂.T₁)/V₁
T₂=(400.298)/568
T₂=209.86 K = -63.1 °C
A 100.0 mLflask is filled with 0.065 moles of A and allowed to react to form B according to the reaction below. The following experimental data are obtained for the amount of A as the reaction proceeds. What is the average rate of appearance of B in units of M/s between t = 10.0 min. and t = 30.0 min.? Assume that the volume of the flask is constant.
The question is incomplete. The complete question is :
A 100.0 mL flask is filled with 0.065 moles of A and allowed to react to form B according to the reaction below. The following experimental data are obtained for the amount of A as the reaction proceeds. What is the average rate of appearance of B in units of M/s between t = 10 min. and t = 30 min.? Assume that the volume of the flask is constant. A(g) → B(g)
Time 0.0 10.0 20.0 30.0 40.0
Moles of A 0.065 0.051 0.042 0.036 0.031
Solution :
Consider the following reaction as follows :
[tex]$A \rightarrow B$[/tex]
The experiment data is given as follows :
Time (min) : 0.0 10.0 20.0 30.0 40.0
Moles of A : 0.065 0.051 0.042 0.036 0.031
According to the rate of reaction concept, the rate can be expressed as a consumption of the reactant and formation of the product as follows :
Average rate : [tex]$= -\frac{d[A]}{dt} = \frac{d[B]}{dt} $[/tex]
Now we have to calculate the average rate between 10.0 to 30.0 min w.r.t. A as follows :
Rate [tex]$=-\frac{(0.051-0.036) mol \times \frac{1}{0.1 \ L}}{(30.0-10.0) mol \times \frac{60 \ s}{1 \ min}}$[/tex]
[tex]$=\frac{0.15 \ M}{20 \ min \times \frac{60 \ s}{1 \ min}}$[/tex]
[tex]$= 1.25 \times 10^{-4 }\ M/s$[/tex]
Therefore, the rate = [tex]$= 1.3 \times 10^{-4 }\ M/s$[/tex]
A 100.0-mL flask is filled with 0.065 moles of A and allowed to react to form B. Between 10.0 min and 30.0 min, the average rate of appearance of B is 1.3 × 10⁻⁴ M/s.
What is the rate of reaction?The rate of reaction is the speed at which a chemical reaction takes place, defined as proportional to the increase in the concentration of a product per unit time and to the decrease in the concentration of a reactant per unit time.
Step 1: Write the balanced equation.A(g) → B(g)
Step 2: Calculate the rate of reaction of A (rate of disappearance of A).To calculate the rate of disappearance of A (rA) between 10.0 min and 30.0 min, we will use the following expression.
rA = -ΔnA / V. Δt = -(0.036 mol - 0.051 mol)/ (0.1000 L) (30.0 min - 10.0 min)
rA = 7.5 × 10⁻³ M/min
where,
ΔnA is the change in the number of moles of A.Δt is the change in time.Step 3: Calculate the rate of reaction of B (rate of appearance of B).The molar ratio of A to B is 1:1.
7.5 × 10⁻³ mol A/L.min × 1 mol B/1 mol A = 7.5 × 10⁻³ mol B/L.min
Step 4: Convert 7.5 × 10⁻³ M/min to M/sWe will use the conversion factor 1 min = 60 s.
7.5 × 10⁻³ M/min × 1 min/60 s = 1.3 × 10⁻⁴ M/s
A 100.0-mL flask is filled with 0.065 moles of A and allowed to react to form B. Between 10.0 min and 30.0 min, the average rate of appearance of B is 1.3 × 10⁻⁴ M/s.
The question is incomplete. The complete question is:
A 100.0 mL flask is filled with 0.065 moles of A and allowed to react to form B according to the reaction below. The following experimental data are obtained for the amount of A as the reaction proceeds. What is the average rate of appearance of B in units of M/s between t = 10 min. and t = 30 min.? Assume that the volume of the flask is constant. A(g) → B(g)
Time (min) 0.0 10.0 20.0 30.0 40.0
Moles of A 0.065 0.051 0.042 0.036 0.031
Learn more about rates of reaction here: https://brainly.com/question/24795637
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Manipulate the settings to model the scenario. Observe what happens to the objects in the stream. Record your
observations in the Lab Guide,
Stream Slope
Gentle
Amount of Rainfall
None
Surrounding Terrain
Plain
Mountains
Check
Pause
Answer:
It causes erosion of the land and stones.
Explanation:
if the objects such as stones etc are present in the way of stream so the stones are eroded due to its fast flowing due to sloppy nature. If the stream is flat then it little disturb the things present in its way because of its lower speed. If more rainfall occur the streams flows in higher speed and destroy everything that comes in its way and also affected the plains.
Answer:this is correct
Explanation:
In the kinetic theory, the particles in a gas
A. move independently of each other.
B. have attractive and repulsive forces.
C. move slowly.
D. are relatively close together.
Answer:
Im pretty sure its B
Sorry if Im wrong
Explanation:
Have a wonderful day!!!<3
Answer:
The only answer that could apply to a gas is A
Explanation:
A chemist prepares a solution of aluminum sulfate by weighing out of aluminum sulfate into a volumetric flask and filling the flask to the mark with water. Calculate the concentration in of the chemist's aluminum sulfate solution. Be sure your answer has the correct number of significant digits.
Answer:
25.8 g/dL
Explanation:
A chemist prepares a solution of aluminum sulfate by weighing out 116.0 g of aluminum sulfate into a 450. mL volumetric flask and filling the flask to the mark with water. Calculate the concentration in g/dL of the chemist's aluminum sulfate solution. Be sure your answer has the correct number of significant digits.
Step 1: Given data
Mass of aluminum sulfate (m): 116.0 gVolume of the solution (V): 450. mLStep 2: Convert "V" to dL
We will use the following conversion factors.
1 L = 1000 mL1 L = 10 dL450. mL × 1 L/1000 mL × 10 dL/1 L = 4.50 dL
Step 3: Calculate the concentration (C) of aluminum sulfate if g/dL
We will use the following expression.
C = m/V = 116.0 g/4.50 dL = 25.8 g/dL
(will give brainliest!! please help me! thank you!)
a) The rows on the periodic table are called periods. How many energy levels are in the atoms of each element in period 2 (lithium-neon)
b) What is the group number of the halogens?
c) What do the elements in each group have in common?
please please help me, i will give brainliest
Answer:
A two energy levels K and L
B halogen are present in group 17
C in same group elements have same valence electrons
Explanation:
I need your help please thank you so much?!?!?
Answer:
The end products cannot be changed back in their original forms
Explanation:
Answer:
the first one
Explanation:
A public School district furnishes pencils to its elementary school. The pencils the secretary orders from the district warehouse each year are packaged in boxes that contain one gross (12 dozen). The average use of pencils is 9.3 pencils per student. If the school's enrollment is 812 students, what is the minimum number of boxes of pencils that should be ordered?
Answer:
The minimum number of boxes of pencils to be ordered is 630 boxes.
Explanation:
Since a pupil uses averagely 9.3 pencils
and a box contains 12 pencils,
the school enrollment is also 812
school's enrollment x average use of pencil per student
__________________________________________
number of pencils in a box
812 x 9.3 = 7551.6
7551.6 /12 = 629.3
Having a total number of 630 boxes of pencils to be ordered.
What is wrong with the following electron configuration?
Answer:
a. without completing 2p stuff...electrons cant go to 3s. the correct configuration is
1s2, 2s2, 2p6, 3s1
b. after 4s, 3d comes not 4d. the correct configuration is 1s2, 2s2, 2p6, 3s2, 4s2, 3d6
c. after 4s, it is 3d and then 4p the correct configuration is 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6.
Hope it helps you 。◕‿◕。
An unknown compound is processed using elemental analysis and found to contain 117.4 g of platinum, 28.91 g of carbon, and 33.71 g of nitrogen. How many moles of platinum are present in the compound? Need help ASAP
Answer:
1 mole of platinum (Pt).
Explanation:
From the question given above, the following data were obtained:
Platinum (Pt) = 117.4 g
Carbon (C) = 28.91 g
Nitrogen (N) = 33.71 g
Number of mole of platinum =?
To obtain the number of mole of platinum present in the compound, we shall determine the empirical formula for the compound. The empirical formula for the compound can be obtained as follow:
Pt = 117.4 g
C = 28.91 g
N = 33.71 g
Divide by their molar mass
Pt = 117.4 /195 = 0.602
C = 28.91 /12 = 2.409
N = 33.71 /14 = 2.408
Divide by the smallest
Pt = 0.602 /0.602 = 1
C = 2.409 /0.602 = 4
N = 2.408 / 0.602 = 4
Therefore, the empirical formula for the compound is PtC₄N₄ => Pt(CN)₄
From the empirical formula for the compound (i.e Pt(CN)₄) we can see that the compound contains 1 mole of platinum (Pt).
How many grams are there in 1.70 moles of KMnO4?
Answer:
269g
Explanation:
hope this helps you
Problem 3 A sample of 2.37 moles of an ideal diatomic gas experiences a temperature increase of 65.2 K at constant volume. (a) Find the increase in internal energy if only translational and rotational motions are possible. (b) Find the increase in internal energy if translational, rotational, and vibrational motions are possible. (c) How much of the energy calculated in (a) and (b) is translational kinetic energy?
Answer:
a) the increase in internal energy is 3211.78 J
b) dU = 3854.14 J
c) dU[tex]_{T}[/tex] = 1927.06 J
Explanation:
Given the data in question;
Foe a diatomic gas, the degree of freedom are as follow;
lets consider the positional degree of freedom
transitional df = 3
rotational df = 2
vibrational ff = 1
now, the internal energy given by;
U = Nf × 1/2NKT = Nf×1/2×nRT
where Nf is the number of degree of freedom
N is Number of atoms or molecules
n = number of molecules
L is Boltzmann constant
R is universal gas constant
so change in internal energy , change in T is given by
dU = Nf × 1/2 × nT dT
n = 2.37 moles
dT = 65.2 K
R = 8.314 J/mol.J
a)
Find the increase in internal energy if only translational and rotational motions are possible
since rotational and transitional motion are involved ;
Nf = 3(trasitional) + 2(rotational) = 5
so,
dU = 5 × 1/2 × nRdT
we substitute
dU = 5 × 0.5 × 2.37 × 8.314 × 65.2
dU = 3211.78 J
Therefore, the increase in internal energy is 3211.78 J
b)
Find the increase in internal energy if translational, rotational, and vibrational motions are possible.
Nf = 3 + 2 + 1 = 6
dU = 6 × 1/2 × nRdT
dU = 6 × 0.5 × 2.37 × 8.314× 65.2
dU = 3854.14 J
c)
How much of the energy calculated in (a) and (b) is translational kinetic energy?
dU[tex]_{T}[/tex] = 3 × 0.5 × 2.37 × 8.314 × 65.2
dU[tex]_{T}[/tex] = 1927.06 J
A solid piece of lead has a mass of 32.00 g and a volume of 2.84 cm^3. From these data, calculate the density of lead in SI units (kilograms per cubic meter).
Answer:
11267.61 Kg/m³.
Explanation:
From the question given above, the following data were obtained:
Mass of lead = 32 g
Volume of lead = 2.84 cm³
Density of lead =.?
Next, we shall convert 32 g to Kg. This can be obtained as follow:
1000 g = 1 Kg
Therefore,
32 g = 32 g × 1 Kg / 1000 g
32 g = 0.032 Kg
Next, we shall convert 2.84 cm³ to m³. This can be obtained as follow:
1 cm³ = 10¯⁶ m³
Therefore,
2.84 cm³ = 2.84 cm³ × 10¯⁶ m³ / 1 cm³
2.84 cm³ = 2.84×10¯⁶ m³
Finally, we shall determine the density of the piece of lead. This can be obtained as follow:
Mass of lead = 0.032 Kg
Volume of lead = 2.84×10¯⁶ m³
Density of lead =.?
Density = mass / volume
Density of lead = 0.032 / 2.84×10¯⁶
Density of lead = 11267.61 Kg/m³
what is the electron configuration for Na?
1s22s22p63s1. That's the ans
In a hotel breakfast bar, you see an older woman sticking a fork into a toaster to remove a piece of toast. You warn her not to do that, and she says, "You know, I always wondered why forks conduct electricity so well." As an astute chemistry student, how would you explain it to her? Make sure you provide a relationship to electronegativity, proton pull, and electron distribution in your answer.
Answer:
See explanation
Explanation:
You see, all these materials we see around us are composed of elements. These elements are unique in their own ways!
Some of them are able to attract tiny negative particles called electrons close to their positive interior called the nucleus. This positive interior is so designated because it contains a positive particle called protons which attract these electrons.
Now, elements are broadly divided into metals and non metals. Protons in metallic elements are less able to pull electrons than protons in non metallic elements. As a result of this, non metals are mostly electronegative because they pull electrons towards themselves while metals are mostly electropositive because they give away their electrons easily. Fork is composed of metallic elements.
Since metals give away electrons easily, they can conduct electricity since electrons are the same charge carriers in electric circuits.
Also, in elements, there is a conduction band and a valence band. Electrons occupy the valence band but also move into the conduction band. The gap between the valence band and the conduction band in nonmetals is large hence they do not conduct electricity. The gap between the valence band and the conduction band in metals is minimal hence metals conduct electricity.
So if you stick that fork into a toaster, electrons can flow right through the toaster circuit into your body and cause you to be electrocuted.
why does mass of popcorn stay the same after popping it
Answer:
Explanation:
it stays the same because the seeds or whatever in the bag was still the pop corn just not fully devloped
g Aqueous hydrobromic acid will react with solid sodium hydroxide to produce aqueous sodium bromide and liquid water . Suppose 57.4 g of hydrobromic acid is mixed with 41. g of sodium hydroxide. Calculate the minimum mass of hydrobromic acid that could be left over by the chemical reaction. Be sure your answer has the correct number of significant digits.
Answer:
Zero
Explanation:
The complete reaction for this is as follows -
HBr + NaOH = NaBr + H2O
1 mole of NaOH reacts with 1 mole of HBr
m(HBr) = 57.4g and M(HBr) = 80.9g/mol
m(NaOH) = 16g and M(NaOH) = 40g/mol
Number of moles = m/M
Substituting the given values we get -
n(HBr) = 57.4 g/80.9 g/mol = 0.709
n(NaOH) = 16 g/40 g/mol = 0.4
n(H2O) = n(NaOH) = 0.40 mol
According to balanced equation
40 gram of NaOH reacts with 81 grams of HBr
41 gram of NaOH will react with 81/40 * 41 = 83.025 gram of HBr
We have only 57.4 g of HBr only hence, 0 HBr will be left.
help now plsss I really need help !!!!
Answer:
4
Explanation:
the one you ARE ON
Atom 1 has 19 electrons 19 protons and 20 neutrons atoms 2 has 19 electrons , 20 neutrons and 19 protons
Answer:
Atom 1: Potassium (K)
Atom 2: Same thing
Explanation:
Potassium has an atomic number of 19 and mass number of 39.0983.
which of the following describes all of the types of water found in the hydrosphere
Answer: all of the water on the Earth
Explanation:
The hydrosphere is made up of all the water that we have on Earth. Included in the hydrosphere are the water that we have underground, those in the Earth's surface, and those that we have in the air.
On Earth, we can find water in the seas, lakes, oceans, streams, rivers etc. Water also comes in form of rain as well.
ASAP I WILL GIVE BRAINLIEST The diagram shows a lever. What is the mechanical advantage of the lever? O 2 03 3 m 6 m mi 0 9
Answer:
A) 2
Explanation:
Answer:
2, i got it right thanks to the other user :) <3
Explanation:
PLZ HELP I WILL GIVE BRAINLISTS TO RIGHT ANSWER
2KCIO3 → 2KCI+ 302
How many moles of oxygen are produced by the decomposition of 5.0 moles of potassium chlorate?
A )7.5 mol O2
B )5.0 mol O2
C )2.5 mol O2
D )9.0 mol O2
Identify the correct statement regarding the mole. a. A mole of oxygen gas contains 6.02 1023 atoms. b. A mole of chlorine gas contains 2 6.02 1023 atoms. c. A mole of carbon dioxide contains two moles of oxygen molecules. d. A mole of ammonia gas (NH3) has a mass of 34.0 g. e. A mole consists of the number of particles in exactly 12 g of naturally occurring carbon.
Answer:
b. A mole of chlorine gas contains 2 (6.02 * 10^23 ) atoms.
c. A mole of carbon dioxide contains two moles of oxygen molecules (CO2)
e. A mole consists of the number of particles in exactly 12g of naturally occurring carbon.
Explanation:
A mole of oxygen gas (O2) contains 2 (6.02 * 10^23) atoms
A mole of Ammonia gas (NH3) has a mass of 17.031g/mol
A mole is defined as the unit used in measurement of the amount of substances in the International System of Units.
A mole was initially defined as the number of particles in exactly 12g of naturally occurring carbon.
Therefore, options b, c and e are correct
1. Consider Reactions 3 and 14 studied in this lab. Write the balanced molecular equation (identical to what you completed in the previous section), the complete ionic equation and the net ionic equation for these reactions. Include all physical states, and circle the spectator ions in the complete ionic equations.
Reaction 3: Aqueous sodium phosphate + aqueous copper(II) sulfate
Balanced Molecular Equation
(from page 1): Complete
Ionic Equation:
Net Ionic Equation:
Reaction 14: Aqueous iron(III) chloride + aqueous ammonium hydroxide
Balanced Molecular Equation
(from page 3): Complete
Ionic Equation:
Net Ionic Equation:
2. Predict the products for the following single and double displacement reactions, and write balanced molecular equations including physical states) for each of them. If you predict that no reaction will occur, write "NR", followed by a brief explanation.
A. Aluminum metal + aqueous silver acetate
B. Aqueous zinc nitrate + aqueous lithium chloride
C. Hydrobromic acid + solid magnesium sulfite
D. Aqueous rubidium hydroxide + perchloric acid
E. Tin metal + phosphoric acid
F. Aqueous lithium chromate + aqueous gold(111) iodide
Answer:
See explanation
Explanation:
For reaction 3;
Molecular equation
2Na3PO4(aq) + 3CuSO4(aq) -----> 3Na2SO4(aq) + Cu3(PO4)2(s)
Complete ionic equation;
6Na^+(aq) + 2PO4^3-(aq) + 3Cu^2+(aq) + 3SO4^2-(aq) ------> 6Na^+(aq) + 3SO4^2-(aq) + Cu3(PO4)2(s)
Net ionic equation;
3Cu^2+(aq) + 2PO4^3-(aq) -----> Cu3(PO4)2(s)
Reaction 14
Molecular equation
2FeCl3(aq) + 6NH4OH(aq) ------>2Fe(OH)3(s) + 6NH4Cl
Complete ionic equation:
2Fe^2+(aq) + 6Cl^-(aq) + 6NH4^+(aq) + 6OH^-(aq) -----> 2Fe(OH)3(s) + 6NH4^+(aq) + 6Cl^-(aq)
Net ionic equation;
2Fe^2+(aq) + 6OH^-(aq) -----> 2Fe(OH)3(s)
2.
Al(s) + 3Ag(CH3COO)(aq) ----->Al(CH3COO)3(aq) + 3Ag(s)
Zn(NO3)2(aq) +2LiCl(aq) ------> 2LiNO3(aq) + ZnCl2(aq)
2HBr(aq) + MgSO3(s) ------>MgBr2(aq) + H2O(l) + SO2(g)
RbOH(aq) + HClO4(aq) -----> RbClO4(aq) + H2O(l)
3Sn(s) + 4H3PO4(aq)----->Sn3(PO4)4(aq) + 6H2(g)
3Li2CrO4(aq) + 2AuI3(aq) -------> 6LiI(aq) + Au2(CrO4)3(s)
Which statement correctly compares electric charge with electric current?
A: They both require a human to make them.
B: Neither require charged particles.
C: They both require a battery and a bulb.
D: They both require a movement of charged particles.
Please help
Answer:
D
Explanation:
i have no explanation ;-;
I checked it with my quiz doe UwU[tex]e[/tex]
first response gets brainliest