Answer:
change in energy of the system = - 21 J
Explanation:
Δu = q + w
q = 364 J
w = - 385
Temperature of system drops from 25°c to 20°c
hence
Δu ( change in energy ) = q - w
= 364 - 385
= -21 J
Solution Mass of NaCl (9) Volume of water (mL)
A
5.0
50.0
B
5.0
75.0
с
5.0
100.0
D
5.0
125.0
Which of the solutions has the highest salt concentration?
O A Solution B
B. Solution A
O
C. Solution C
D. Solution D
Divide the volume of water with mass of salt and multiply with 100 you'll get the concentration percentage
answer is B, because solution A's percentage is 10%
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To prepare a buffer solution with a pH of 4.1, which acid should be used?
glycine: pka = 2.35
benzoic acid: pka = 4.19
hydrobromous: pKa = 8.7
Answer:
benzoic acid: pka = 4.19
Explanation:
what is a mole and its properties
One mole of a substance is equal to 6.022 × 10²³ units of that substance (such as atoms, molecules, or ions). The number 6.022 × 10²³ is known as Avogadro's number or Avogadro's constant. The concept of the mole can be used to convert between mass and number of particles.
the form of EMR that has less energy per photon than microwaves is ____?
Answer: radio wave frequencies have longer wavelengths and smaller
Energies per photon
i What
What is ment by
ment by covalency?
How many fluorine atoms are there in 39.4 moles of CF4?
Answer:
here
Explanation:
Answer: 4
A molecule of carbon tetrafluoride, CF4 , is made up of 1 carbon atom bonded to 4 fluorine atoms. Each carbon atom weighs 12.0 amu and each fluorine atom weighs 19.0 amu so 1 CF4 molecule weighs 1×12.0 amu + 4×19.0 amu = 88.0 amu. This number, 88.0, is called the molecular weight (or molecular mass) of CF4.
What is the molality of a 10.0 % by mass solution of NaCl?
(molar mass of NaCl = 58.44 g/mol)
mol/kg
On CK-12 all of these answers are correct
1.9
1.888
1.89
1.88
The molality of a 10.0 % by mass solution of sodium chloride (NaCl) is 1.7M.
How do we calculate molarity?Molarity of any solution will be calculated as number of moles of solutes present in per litre of the solution.
Moles of the substance will be calculated as:
n = W/M, where
W = given mass
M = molar mass
Given that percent mass of NaCl = 10% i.e. 10g of NaCl is present in 100 g of solution.
We know that 1 g = 0.001 L
100 g = 0.1 L
Moles of NaCl = 10g / 58.44g/mol = 0.17 mol
Molarity of NaCl = 0.17 / 0.1 = 1.7M
Hence required molarity is 1.7 M.
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If 22.4L = I moles How many liter of CO2 are produced if you produce 9.6 moles of CO2?
Answer:
215 moles
Explanation:
[tex]9.6mol CO_{2} (\frac{22.4 L CO_{2}}{1 mol CO_{2}} ) = 215 L CO_{2}[/tex]
You have 281 kilojoules how many kilocalories is it need to know ASAP
Rank the following compounds in order of increasing solubility in water. Items (4 items) (Drag and drop into the appropriate area) No more items Items in order most soluble CaO BaO KCI KI
I have tried CaO> BaO > KCl > KI, this is incorrect.
Answer:
CaO < BaO < KCl <KI
Explanation:
Let us remember that the solubility of an ionic substance in water depends on the magnitude of the lattice energy and the hydration energy. If the hydration energy is equal to or is greater than the lattice energy, the substance dissolves in water.
However, the lattice energy depends on the size of the ions. The smaller the ions in the ionic compound, the higher the lattice energy and the lesser the solubility of the ionic compound.
KI has the least lattice energy and the highest solubility in water while CaO has the highest lattice energy and the least solubility in water.
Of the three Intermolecular forces, the type with the largest dissociation energy is ________.
A. Dipole-dipole interactions
B. Dispersion forces
C. Hydrogen bonds
Answer:
C. Hydrogen bonds
Explanation:
Strongest intermolecular force
Hydrogen Bonding (H-Bonding)
Hydrogen bonds are caused by highly electronegative atoms. They only occur between hydrogen and oxygen, fluorine or nitrogen, and are the strongest intermolecular force.
Answer: C hydrogen bonds
Explanation:
Is the Swedish timber industry more likely a result of good resource availability or a lack of trees elsewhere on Earth?
Answer:
The forest products industry plays a major role in the Swedish economy, and accounts for between nine and 12 percent of Swedish industry's total employment, exports, sales and added value. It includes companies within the pulp and paper industry, as well as the wood-mechanical industry.
What is the hydrogen ion concentration ([H']) of a substance with a pH of 4.91?
Answer:
The pH of a solution is a measure of the concentration of hydrogen ions in the solution. A solution with a high number of hydrogen ions is acidic and has a low pH value. A solution with a high number of hydroxide ions is basic and has a high pH value. The pH scale ranges from 0 to 14, with a pH of 7 being neutral.
There are eight diastereomers of 1,2,3,4,5,6-hexachlorocyclohexane. One of them is drawn. Draw the other seven in the cyclohexane framework below (5 points). One isomer loses HCl in an E2 reaction nearly 1000 times more slowly than the others. Circle the isomer that reacts so slowly, draw its corresponding chair conformers and explain the reason for the slow rate. (5 points).
Answer:
Attached below diagram of the eight diastereomers
The Isomer that reacts so slowly is DIASTEREOMER 8
Explanation:
The Isomer that reacts so slowly is DIASTEREOMER 8 in an E2 reaction and this is because no pair of chlorine and hydrogen atoms can assume the anti-periplanar orientation that is preferred in an E2 elimination
attached below is Diagram of the eight diastereomers ( screen shot from my drawing tool )
What is the correct chemical name for N3H4
Answer:
Molar mass of N3H4 name is 84.0761 g/mol
Convert between N3H4Na(CH3) weight and moles
The chemical name for the formula N₃H₄ is Trinitrogen Tetrahydride
How a chemical compound is named ?The first element is named by simple using the name of the element. The second element is named by taking the stem of the element name and adding the suffix -ideThe element that is less electronegative is written first ,there are exceptions like , Carbon is always first in a formula and hydrogen is after nitrogen in a formula such as NH3 . The sequence of common nonmetals in binary compound is
C , P , N , H , S , I , Br , Cl , O , F .
So Now for N₃ = Tri Nitogen
and for H₄ = Tetra Hydride
Therefore the chemical name is Trinitogen Tetrahydride.
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what climate is Colorado in?
A.Most Subtropical Mid-Latitude
B.Polar
C.Moist ContinentaMid-Latitiude
D.Dry
Answer:
b
Explanation:
Answer:
D. Dry
Explanation:
Colorado's combination of high elevation, midlatitude, and continental interior geography results in a cool, dry climate.
MATch THE BOXED PLEASEEEE
Answer:
Transform = The third one
Convergent = the first one
Divergent = the second one
Explanation:
anyone help with the percent yield questions?
Answer:
oof this is way to hard sry man
Explanation:
How many grams of ( S ) - 1 - chloro - 4 - ethyl - 2 - methylhexane and triphenylphosphine would you need to create 4 . 1 5g of ( S ) - 1 - chloro - 4 - ethyl - 2 - methyl triphenylphosphonium assuming an 8 1 % yield for the reaction?
Answer:
Explanation:
The standard molar mass is:
For (S )-1-chloro-4-ethyl-2-methylhexane = 162.5 g/mol
For triphenylphosphine = 262 g/mol
For ( S )-1-chloro-4-ethyl-2-methyl triphenylphosphonium = 424.5 g/mol
The mass required for 81% yield = [tex]\dfrac{81}{100} \times Theoretical \ yield = 4.15 g[/tex]
Theoretical yield = [tex]\dfrac{4.15}{0.81}[/tex]
= 5.1235 g
thus, since 424.5 g yield produce from 162.5 g
∴
5.1235 g yield will produce = [tex]\dfrac{162.5}{424.5}\times 5.1235 \ g[/tex]
= 1.9613 g of alkyl halide (-chloro) required.
Also, since 424.5 g yield produce from 262 g phosphine
∴
5.1235 g yield will produce = [tex]\dfrac{262}{424.5}\times 5.1235 \ g[/tex]
= 3.1622 g of triphenylphosphine required.
How many grams are in 1.2 x 1024 atoms of sodium?
Answer:
46 g
Explanation:
First we convert 1.2 x 10²⁴ atoms of sodium into moles, using Avogadro's number:
1.2x10²⁴ atoms ÷ 6.023x10²³ atoms/mol = 2.0 molThen we convert 2.0 moles of sodium into grams, using sodium's molar mass:
2.0 mol Na * 23 g/mol = 46 gThus, there are 46 grams in 1.2x10²⁴ atoms of sodium.
This timeline woulchre useful to someone who was writing a report titled
What is the concentration of a 500 mL solution with 25 mol of HF? Write your answer with TWO decimal places and round accordingly.
Answer:
oop I'm thinking hmmmmm
is the sun the only star in our solar system
Answer:
Hey mate......
Explanation:
This is ur answer.......
The largest star, and indeed the only star in our solar system, is the sun. The sun is a bit under a million miles across. About 110 Earths put side by side would equal the size of the sun. The sun has 99.8 percent of the mass of our solar system.
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You have three containers each of which is connected to a fourth empty container. Three of the containers contain pure gases. In the first container oxygen is at 2 atm, nitrogen at 4 atm is in the second container, and argon at 1 atm is in the third. When you open the valve and mix the gases in the forth container, what is the pressure, PT, in the forth container
Answer: The total pressure is 7 atm
Explanation:
According to Dalton's law, the total pressure is the sum of individual pressures.
[tex]p_{total}=p_A+p_B+p_C...[/tex]
Given : [tex]p_{total}[/tex] =total pressure of gases = ?
[tex]p_{O_2}[/tex] = partial pressure of oxygen = 2 atm
[tex]p_{N_2}[/tex] = partial pressure of nitrogen = 4 atm
[tex]p_{Ar}[/tex] = partial pressure of argon = 1 atm
putting in the values we get:
[tex]p_{total}=2atm+4atm+1atm[/tex]
[tex]p_{total}=7atm[/tex]
Thus the total pressure is 7 atm
what is the molecular formula of a compound with the empirical SO and molecular weight 96.13?
Answer:
Explanation: A compound with the empirical formula SO has a molecular weight of 96.13
I don’t understand please help
Which of the following is a homogeneous mixture ?A.pizza B.oxygen
C.tea
D .pure water
I think it would be d bc water is everywhere
Is this equation balanced: AgNO3 + 2 KCl -->AgCl + KNO3 Yes No
Answer:
No
Explanation:
AgNO₃ + KCl --> AgCl + KNO₃
This reaction is a precipitation reaction. AgCl is formed as a white solid due to its low solubility in water.
In Which State of matter are molecules moving the slowest
A. Solid
B. Liquid
C. Gas
Answer:
Solid
Explanation:
Molecules in solids only vibrate in place, while the other two have moving molecules
What is a similarity between a fish embryo and a human embryo in the late stages of development?
They both have tails
They both have gills.
They both have spines.
They both have arms.
Answer:In the LATER stages of development they would have a spine
Explanation: