Answer:
(a) [tex]\Delta H=-73.1\frac{kJ}{mol}[/tex]
(b) [tex]T_2=38.1\°C[/tex]
(c) Yes, it is appropriated.
Explanation:
Hello.
(a) In this case, given the formation enthalpies for copper (II) sulfate, copper (II) ion and sulfate ion, we can compute the enthalpy change for such process as follows:
[tex]\Delta H=\Delta H_{Cu^{2+}}+\Delta H_{SO_4^{-2}}-\Delta H_{CuSO_4}\\\\\Delta H=64.8-909.3-(-771.4)\\\\\Delta H=-73.1\frac{kJ}{mol}[/tex]
(b) In this case, since 13.0 g of copper (II) sulfate (molar mass: 159.55 g/mol) we can compute the gained heat by water via:
[tex]Q_{water}=-n_{CuSO_4}\Delta H=-13.0g*\frac{1mol}{159.55g}* -73.1\frac{kJ}{mol}\\ \\Q_{water}=5.96kJ=5960J[/tex]
As the heat lost by the reaction is gained by the water, therefore, the final temperature is:
[tex]Q_{water}=m_{water}Cp_{water}(T_2-T_1)\\\\T_2=T_1+\frac{Q_{water}}{m_{water}Cp_{water}}\\ \\T_2=25.0\°C+\frac{5960J}{0.109L*\frac{1000g}{1L}*4.18\frac{J}{g\°C} } \\\\T_2=38.1\°C[/tex]
(c) In this case, since this dissolution reaction is exothermic as it increases the temperature when undergone, we can infer that yes, this dissolution would be appropriate for the preparation of a hot pack, because a cold pack would be with an endothermic dissolution reaction.
Best regards.
12. What is the frequency of a photon with an energy of 3.03 x 10-19 J?
(Planck's constant: h=6.63x 10-34 J·s) (E =hu)
a. 1.98x10^-18 Hz
b. 4.58x10^14 Hz
c. 2.16x10^14 Hz
d. 4.39x10^-19 Hz
Answer:
[tex]u=4.57x10^5GHz[/tex]
Explanation:
Hello.
In this case, given the formula:
[tex]E=h*u[/tex]
Whereas E is the energy, h the Planck's constant and u the frequency of the photon. Thus, solving for it, we obtain:
[tex]u=\frac{E}{h}=\frac{3.03x10^{-19}J}{6.63x10^{-34}J*s}\\ \\u=4.57x10^{14}s^{-1}[/tex]
Or also:
[tex]u=4.57x10^{14}Hz*\frac{1GHz}{1x10^9Hz}\\ \\u=4.57x10^5GHz[/tex]
Best regards.
3. Where are gastropods found? Choose all the correct answers.
A) on land
OB) in salt water
OC) in fresh water
OD) all of the above
O E Maastropods are extinct
Save
Answer:
OD
Explanation:
they live in every habitat on Earth. Marine habitats, ocean basins, freshwater habitats, and inland equatic habitats including salt lakes.
Calculate the energy of a wave given a frequency of
9.43 x 1011 Hz.
Answer:
The answer is
[tex]4.92 \times {10}^{ - 22} \: J[/tex]
Explanation:
In order to find the energy of the wave we use the formula
e = hfwhere
e is the energy
f is the frequency
h is the Planck's constant which is
6.626 × 10-³⁴ Js
From the question
f = 9.43 × 10¹¹ Hz
We have
[tex]e = 9.43 \times {10}^{11} \times 6.626 \times {10}^{ - 34} \\ [/tex]
We have the final answer as
[tex]4.92 \times {10}^{ - 22} \:J[/tex]
Hope this helps you
A 4.534 g sample of a solid mixture was analyzed for barium ion. First the rock was crushed in a mortar and pestle. 100% of the sample was transferred to a beaker, where it was dissolved in 150.0 mL of d.i. water. to give 152 mL of solution. The aqueous sample was then analyzed by adding a small excess of sulfuric acid. The resultant reaction produced a precipitate of barium sulfate, which was collected by filtration, rinsed, dried and weighed. If 0.5376 g of barium sulfate was obtained, what was the mass percent of barium in the original sample? What was the molar concentration barium in the 152 mL of solution prior to adding sulfuric acid? Show work clearly; include a balanced net ionic chemical equation, units and sig. figs.
Answer:
6.976%
0.0152 M
Explanation:
Step 1: Write the balanced chemical equation
Ba²⁺(aq) + H₂SO₄(aq) ⇒ BaSO₄(s) + 2 H⁺(aq)
The balanced net ionic chemical equation is:
Ba²⁺(aq) + SO₄²⁻(aq) ⇒ BaSO₄(s)
Step 2: Calculate the moles corresponding to 0.5376 g of BaSO₄
The molar mass of BaSO₄ is 233.39 g/mol.
0.5376 g × (1 mol/233.39 g) = 2.303 × 10⁻³ mol
Step 3: Calculate the moles of Ba²⁺ that produced 2.303 × 10⁻³ moles of BaSO₄
The molar ratio of Ba²⁺ to BaSO₄ is 1:1. The moles of Ba²⁺ are 1/1 × 2.303 × 10⁻³ mol = 2.303 × 10⁻³ mol.
Step 4: Calculate the mass corresponding to 2.303 × 10⁻³ moles of Ba²⁺
The molar mass of Ba²⁺ is 137.33 g/mol.
2.303 × 10⁻³ mol × 137.33 g/mol = 0.3163 g
Step 5: Calculate the mass percent of barium in the original sample
0.3163 g of barium ion were in a 4.534 g-sample. The mass percent of barium ion is:
0.3163 g/4.534 g × 100% = 6.976%
Step 6: Calculate the molar concentration barium in the 152 mL of solution
2.303 × 10⁻³ moles of barium ion were in 152 mL (0.152 L) of solution. The molarity of barium ion is:
M = 2.303 × 10⁻³ mol/0.152 L = 0.0152 M
Which of the following items would improve the experiment? Add more types of plants Test one plant with no fertilizer Use different soils for each plant Expose all six plants to green light
Answer:
Um, I'd say add more types of plants cause different plants react differently to things, I guess?
Determine the milliliters of paint in a 5.0 gallon bucket
Ans: 18950 ML
Answer:
the answer is 18,927,06.
Explanation:
I just took the test ; )
How many oxygen atoms are in 8.20 g Na 2SO 4?
Answer:
No. of atom =
no.of moles x avagardro's number xatomicity
= weight /molar mass x No x atomicity
=8.2/142 x6.02x10^23 x 4
=0.346 x 10^23(approximately)
How many total atoms are in one molecule of maltose?
Answer:
The total number of atoms is 12 + 22 + 11 = 45, so carbon atoms are 12/45 of the total.
Explanation:
* 20 POINTS
A ________ is made of two or more elements chemically combined.
a.
alloy
b.
mixture
c.
element
d.
compound
Answer:
Compound is the answer
do it if u trust urself
Which statement provides the complete explanation of how renewable and nonrenewable resources differ?
They differ in the amount they are found in nature.
They differ in the rate they are replaced.
They differ in the available amount and rate they are used and replaced.
They differ in the rate they are used.
Answer:
They differ in the available amount and rate they are used and replaced.
Explanation:
If one material is replaceable, then it's renewable. If it's not replaceable, then it's non-renewable.
The statement 'they differ in the available amount and rate they are used/replaced' provides an explanation of how renewable and nonrenewable resources differ.
What are renewable resources?Renewable resources can be defined can natural resources that can be renowned in nature in a given period of time.
These renewable resources include biomass and different types of energies (geothermal, wind, solar, etc). Conversely, non-renewable resources are specific resources from nature that cannot be replaced (e.g., coal).In conclusion, the statement 'they differ in the available amount and rate they are used/replaced' provides an explanation of how renewable and nonrenewable resources differ.
Learn more about renewable resources here:
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Using Beer's Law determine the concentration of a dye dissolved in water that has an absorptivity of 1 x 102 cm-1M-1 and produces an absorbance reading 1.0. The length of the cuvette is 1 cm.
Answer:
1 × 10⁻² M
Explanation:
Step 1: Given data
Absorptivity of a dye (ε): 1 × 10² cm⁻¹M⁻¹
Absorbance (A): 1.0
Length of the cuvette (l): 1 cm
Concentration of a dye (C): ?
Step 2: Calculate the concentration of the dye
We will use Beer's Law.
A = ε × l × C
C = A / ε × l
C = 1.0 / 1 × 10² cm⁻¹M⁻¹ × 1 cm
C = 1 × 10⁻² M
The concentration of the dye is 1 × 10⁻² M.
You were tasked to check if the liquid sample you have is a substance or a
mixture. Which among these tests is the BEST way to do so?l.color comparizon
lltaste comparizon
III. Boiling Test
IV. Melting Test
a.I, II, III and IV. b.l,II, and III only
c. I and Ill only
d. I, II, and IV only
Answer:
The correct answer is - option C. I and Ill only.
Explanation:
One never tastes a unknown chemical in chemistry lab especialy a liquid that can be hazardous. Melting test is for solid as a solution is already a liquid state so melting test can not be perform on it.
The two test can be perform on given sample that are color comparison and boiling test to check if it is substance or a mixture. A misture is prepared from mixing different kind of compounds that can give different kind of color while a particular substance give a uniform color always or remain colorless.
Boiling test can be helpful in distinguish a mixture from a substance as a particular sybstance always give a particular boiling point but mixture can be varry and depend of the coponents mixed together
Which of the following describes a chemical change?
A. a suspension of corn starch and water
B. formation of a precipitate
C. formation of a solution
D. filtration of a solid from a liquid
Answer:
C
Explanation:
Have a nice day
Classify the sugars as either aldoses or ketoses. A Fischer projection with a six carbon backbone. Carbon one is an aldehyde and carbon six is part of the group C H 2 O H. Carbons two and three have an hydroxide group on the left, and carbons four and five have an hydroxide group on the right. A Fischer projection of a six carbon backbone. Carbons one and six are part of a C H 2 O H group. Carbon two is attached to a ketone, carbons three and four have a hydroxide group on the left, and carbon five has a hydroxide group on the right. A Fischer projection with a five carbon backbone. Carbon one is an aldehyde, carbon five is part of the group C H 2 O H, and carbons two through four have an hydroxide group on the right. A Fischer projection with a three carbon backbone. Carbon one is an aldehyde, carbon three contains the group C H 2 O H, and carbon two has a hydroxide group on the right. A Fischer projection with a five carbon backbone. Carbons one and five are part of a C H 2 O H group. Carbon two is attached to a ketone and carbons three and four have a hydroxide group on the right. A Fischer projection of a four carbon backbone. Carbons one and four are part of a C H 2 O H group. Carbon two is attached to a ketone and carbon three has a hydroxide group on the right. Answer Bank
Answer AND Explanation: Carbohydrates or sugars have three classes:
Monossaccharides: made from a single polyhydroxy aldehyde or ketone unit;Oligosaccharides: formed by short chains of monossacharides united by glycosidic linkage;Polysaccharides: consist of a long chain of monossaccharides;Monossaccharides are formed by a chain of unbranched carbon, all bonded by single bonds, except for a carbon that is double-bonded by an oxygen. This bond form a carbonyl group.
If the carbonyl is at an end of the chain, the carbon is aldehyde and the molecule is called aldose. If the group is in any other position, it is a ketone and is called ketose
So analysing each projection:
1) Carbon one is a aldehyde, which means is a carbonyl and there are no other carbons forming that bond, so it's a ALDOSE
2) Carbon two is attached to a ketone and other carbons aren't, so it's a KETOSE.
3) Carbon one is aldehyde, so it's ALDOSE
4) Carbon one is aldehyde, so ALDOSE
5) Carbon two is attached to ketone, so KETOSE
6) Carbon two attached to a ketone, so KETOSE
3. Describe the trends in atomic size, ionization energy, and electronegativity from left to right across a period in
the periodic table.
Answer:
Atomic size increase with increasing atomic number within a group.
Atomic size decrease with increasing atomic number across a period.
The statement, that describe the trends in atomic size, ionization energy, and electronegativity is "that atomic size decreases, ionization energy and electronegativity increases."
What is atomic size?Atomic size seems to be the space between an atom's nucleus and its outermost shell.
What is ionization energy?The energy necessary to remove the highest-energy electron from a neutral atom is known as ionization energy (IE).
What is electronegativity?Electronegativity is a chemical property that describes an atom's or functional group's inclination to draw electrons toward itself. Across a period of elements, atomic size falls steadily from left to right. This is because all electrons within a period or family of elements are added to the same shell. Ionization energy generally increases across a period and declines down a group.
Electronegativity normally increases as you move from left to right across a period and decreases as you move down a group on the periodic table.
Hence the correct answer is atomic size decreases, ionization energy and electronegativity increases.
Learn more about atomic size , ionization energy and electronegativity
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What is the smallest particle of matter called?
Answer:
an atom and inside the atom are protons electrons and nuetrons
Explanation:
Answer:
An Atom
Explanation:
An atom is the most smallest particle of matter, you can't see with the most powerful telescopes or microscopes
Determine the number of liters in a 355 milliliter can of soda.
Ans: 0.355 L
What would be the formal charge of N in NO2?
Answer:
What would be the formal charge of N in NO2?
Explanation:
The nitrogen gets two electrons for the double bond, one from the single bond and one from the half-filled orbital associated with it. That's a total of 4 and gives N a +1 formal charge since itneeds 5 to be neutral. The Rules for Writing Lewis Structures has some discussion of formal charge in it.
Which process squeezes layers of sediment together?
compaction
deposition
erosion
weathering
Answer:
The answer is compaction.
Explanation:
what is the formula for sodium hydrogen phosphate
Answer: Na2HPO4
Explanation: this is the formula
Answer:
Na3PO4
Explanation:.
Which of the following is least like the others on the list?
a. Glucose
b. Glycogen
c. Sucrose
d. Catalase
Answer:
catalase
Explanation:
catalase is enzime the rest are glucides
How many moles of carbon are produced When 1745g of sugar react according to the equation C6H12O6+ H2SO4 to 6C +6H2O
Answer:
Number of moles of C produced = 58.08 mol
Explanation:
Given data:
Mass of sugar = 1745 g
Moles of C produced = ?
Solution:
Chemical equation:
C₆H₁₂O₆ + 6H₂SO₄ → 6C + 6(H₂SO₄.H₂O)
Number of moles of sugar:
Number of moles = mass/molar mass
Number of moles = 1745 g/180.16 g/mol
Number of moles = 9.68 mol
Now we will compare the moles of C and sugar.
C₆H₁₂O₆ : C
1 : 6
9.68 : 6×9.68 = 58.08 mol
Number of moles of C produced = 58.08 mol
which surface events are examples of weathering
Answer:Weathering Erosion & Deposition
Changes in shape, size, and texture of land-forms (i.e. mountains, riverbeds, and beaches)
Landslides.
Buildings, statues, and roads wearing away.
Soil formation.
Washes soil, pollutants, harmful sediments into waterways.
Causes metals to rust.
Reduces beaches, shorelines.
Delta formation.
Explanation:
Which properties makes a metal a good material to use for electrical wires?
A. Malleability and reactivity
B. Conductivity and ductility
C. Ductility and malleability
D. Reactivity and conductivity
Answer:
D
Explanation:
Because a metal must reactive and able to conduct
Answer:
B.Conductivity and ductility
Explanation.
Some metals are conductive and are ductile
Conductivity is the ability to have an electric flow
Ductility is the ability to bend
Match the term with the definition. (4 points)
Column A
1.
Liquid
:
Liquid
2.
Plasma
:
Plasma
3.
Solid
:
Solid
4.
Gas
:
Gas
Column B
a.
has lots of space between the charged particles
b.
has lots of space between particles and is easily compressible
c.
flows easily but is difficult to compress
d.
does not flow easily and is difficult to compress
Answer:
1 - does not flow easily and is difficult to compress
2 -does not flow easily and is difficult to compress.
3 -has lots of space between the charged particles.
4-flows easily but is difficult to compress.
Explanation:
HELP ASAP!!!........
What is cheese made of is it like a piece of moon ?!
Answer:
It's made from dairy.
Explanation:
Element Rand Element Q have the same number of valence
electrons. These elements both have similar chemical behavior, but
Element R has fewer energy levels than Element Q. Which statement best
describes the positions of the two elements in the periodic table?
I know I'm answering super late, but I just want to help others who don't know the answer
Answer:
H. The two elements are in the same group, with Element R just above Element Q.
Explanation:
When answering a question like this, I would highly recommended using a periodic table. I used a periodic table to find the answer to the question.
Which statement best explains why gases are poor conductors of thermal energy?
Answer:
Thermal Insulators
That's because air, like other gases, is a poor conductor of thermal energy. The particles of gases are relatively far apart, so they don't bump into each other or into other things as often as the more closely spaced particles of liquids or solids
Explanation:
PLEASEEEEEEEEEEEEEEEEEEEE im slow i'll give you brainliest if you answer idkk what to do
a group of atoms bonded together, representing the smallest fundamental unit of a chemical compound that can take part in a chemical reaction.
Compound:A compound is a material formed by chemically bonding two or more chemical elements. The type of bond keeping elements in a compound together may vary: covalent bonds and ionic bonds are two common types. The elements are always present in fixed ratios in any compound.
Element:Chemical element, also called element, any substance that cannot be decomposed into simpler substances by ordinary chemical processes. Elements are the fundamental materials of which all matter is composed.
Mixture:is a material made up of two or more different substances which are physically combined.
Chemical Formula:A chemical formula identifies each constituent element by its chemical symbol and indicates the proportionate number of atoms of each element. I
Pure substance:A substance that has a fixed chemical composition throughout is called a pure substance such as water, air, and nitrogen.
hope this help!
Answer:
Here are the definitions of all of them.
Explanation:
Molecule:
a group of atoms bonded together, representing the smallest fundamental unit of a chemical compound that can take part in a chemical reaction.
Compound:
A compound is a material formed by chemically bonding two or more chemical elements. The type of bond keeping elements in a compound together may vary: covalent bonds and ionic bonds are two common types. The elements are always present in fixed ratios in any compound.
Element:
Chemical element, also called element, any substance that cannot be decomposed into simpler substances by ordinary chemical processes. Elements are the fundamental materials of which all matter is composed.
Mixture:
is a material made up of two or more different substances which are physically combined.
Chemical Formula:
A chemical formula identifies each constituent element by its chemical symbol and indicates the proportionate number of atoms of each element. I
Pure substance:
A substance that has a fixed chemical composition throughout is called a pure substance such as water, air, and nitrogen.
