Answer:
An element's mass number (A) is the sum of the number of protons and the number of neutrons. The small contribution of mass from electrons is disregarded in calculating the mass number.
How much of a 0.250 M sucrose solution must be used to prepare 400.0 mL of a 0.0310 M solution? mL
Answer:
49.6 mL
Explanation:
is the answer, I just did it :)
49.6mL of a 0.250 M sucrose solution must be used to prepare 400.0 mL of a 0.0310 M solution.
What is Molarity?Molarity of a given solution is known as the total number of moles of solute per litre of the solution. A solution that is 1.00 molar (written 1.00 M) contains 1.00 mole of solute for every liter of solution.
Molarity = (No. of moles of solute ÷ Volume of solution in liters)
The unit of molarity is mol L⁻¹.
Molarity is temperature dependent because as temperature changes, volume of the solution also changes.
We can also use the formula-
M1V1 = M2V2
M1 = 0.25
V2 = 400mL
M2 = 0.0310
V1 = ?
V1 = M2V2/ M1
V1 = 49.6mL
Therefore, 49.6mL of a 0.250 M sucrose solution must be used to prepare 400.0 mL of a 0.0310 M solution.
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What mass of iron (ciron= 0.11 cal/g°C) would need 1450 cal of energy in order to raise its temperature by 19.7°C
Answer: m=Q/c*\Delta TQ/c∗ΔT = 1450cal/(0.11cal/g* 19.7ºC)=669.12 g1450cal/(0.11cal/g∗19.7ºC)=669.12g
Answer: 669.12g iron.
Explanation:
Balance the equation :
CoBr3 + CaSO4
please define how many atoms each element contain
Answer:
im not 2100][dskcmaln,NMCS KHJBXsjk[pl,;maxkcjxnxxxxxxxxxxxxxas'j
Explanation:
mnkc
determine the molar mass of water. WRITE THE UNITS
A rod, X has a positive charge of 8. An otherwise identical rod, Y has a negative charge of 4. The rods are touched together, and then separated.
1.When they touch, what particles move between them?
2.Did the particles move from "X" or "Y" or from "Y" to "X"?
Answer:
1. electrons
2. From "Y" to "X"
Explanation:
1. Electrons move between the rod since the electrons are the only charge carriers which are free to move.
2. The particles move from from "Y" to "X" since the electrons are the only charge carriers which are free to move. The positive charge on rod x is due to a deficit of electrons while the negative charge on rod Y is due to the excess of electrons. When the rods come together, the electrons move from "Y" to "X" since the electrons are the only charge carriers which are free to move.
write the chemical equation for the reaction of monohydrogen phosphate ion, hpo42− , with water.
The chemical equation for the reaction of the monohydrogen phosphate ion (HPO₄²⁻) with water (H₂O) is: HPO₄²⁻ + H₂O → H₂PO₄⁻ + OH⁻
In this reaction, the monohydrogen phosphate ion reacts with water to form dihydrogen phosphate (H₂PO₄⁻) and hydroxide ion (OH⁻). The monohydrogen phosphate ion donates a proton (H⁺) to a water molecule, resulting in the formation of the dihydrogen phosphate ion.
Simultaneously, the water molecule accepts the proton, leading to the production of the hydroxide ion. This reaction can occur because the monohydrogen phosphate ion is amphoteric, meaning it can act as both an acid and a base.
The resulting products, dihydrogen phosphate and hydroxide ions, contribute to the pH and ionic balance in aqueous solutions.
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if the isentropic efficiency of the turbine is 80%, calculate the actual work output of the turbine, in kj/kg.
The required actual work output of the turbine is 1.2 Mj/kg.
If the isentropic efficiency of the turbine is 80%, calculate the actual work output of the turbine, in kj/kg.A steam turbine receives steam at a particular pressure and temperature and discharges it at a lower pressure and temperature. In general, the steam turbine's work output is less than the maximum possible work output, which is known as the isentropic turbine work output. The ratio of the actual turbine work output to the isentropic turbine work output is known as the isentropic turbine efficiency.ηt = Wtisentropic/WtactualWhere,ηt = isentropic turbine efficiencyWtisentropic = isentropic turbine work outputWtactual = actual turbine work outputGiven, isentropic efficiency of the turbine is 80%.ηt = 80% or ηt = 0.8We know thatWtactual = ηt x Wtisentropicor Wtisentropic = Wtactual/ ηtWe also know thath1 = 3.6 Mj/kgh2 = 2.1 Mj/kghence,Δh = h1 - h2 = 3.6 - 2.1 = 1.5 Mj/kgNow we have, Wtisentropic = Δh = 1.5 Mj/kgWtactual = ηt x Wtisentropic = 0.8 x 1.5= 1.2 Mj/kgTherefore, the actual work output of the turbine is 1.2 Mj/kg.
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How many molecules are in
6.0 moles of methane (CH4)?
Let's begin by setting up our equation.
What belongs in the green box?
6.0 moles CHA
A. 1 mole CH4
B. 6.02 x 1023 molecules CH4
a) Water has a molar mass of 18 g/mol and a density of 1000 kg/m3 (or 1 g/cm3). Based on this data, estimate the number of water molecules per unit surface area of water.
b) The coordination number of water (i.e., the average number of "neighbors" each water molecule has) in the liquid state is 4. Neighboring water molecules attract each other via hydrogen bonds, each of which has a binding energy of roughly 10–20 J (although this number depends relatively strongly on temperature). Use this information to estimate the surface tension of water. How does your estimate compare to the observed figure (
γ water = 0.072 N/m ) (hints: Keep in mind that we can think of
surface tension as surface energy per unit area, and consider the energy needed to bring a molecule from the bulk to the surface)?
The estimate is still useful because it provides insight into the behavior of water molecules at the surface of the liquid.
Molar mass of water, M = 18g/molDensity of water, ρ = 1g/cm³ = 1000kg/m³The number of molecules per unit surface area of water can be estimated as follows:Number of water molecules per unit volume of water = Avogadro's number, NA / MNumber of water molecules per unit volume of water = 6.022 × 10²³ / 18 = 3.345 × 10²² / molThe number of molecules per unit surface area of water = the number of molecules per unit volume of water × the thickness of the water layer on the surface= 3.345 × 10²² / m³ × 1 × 10⁻⁸ m= 3.345 × 10¹⁴ / m²b)Given:Coordination number of water, CN = 4Binding energy of hydrogen bond, E = 10⁻²⁰ JThe surface tension of water, γ water = 0.072 N/mEnergy required to bring one molecule from the bulk of the liquid to the surface of the liquid, ΔE= γ water × AThe total binding energy of a water molecule in the liquid state = the binding energy of one hydrogen bond × the coordination number= 10⁻²⁰ J/bond × 4 bonds = 4 × 10⁻²⁰ JThe number of molecules per unit surface area of water = the energy required to bring one molecule from the bulk of the liquid to the surface of the liquid / the total binding energy of a water molecule in the liquid state= ΔE / 4 × 10⁻²⁰= 0.072 / (4 × 10⁻²⁰)= 1.8 × 10²⁰The surface tension of water can also be expressed as follows:γ water = (N / A) × EThe number of hydrogen bonds per unit area, N / A = γ water / E= 0.072 / 10⁻²⁰ = 7.2 × 10¹⁸ / m²The difference between the estimated value and the observed value is relatively large (about a factor of 25). It is because this is just an estimate, and it does not consider all the factors affecting the surface tension of water. However, the estimate is still useful because it provides insight into the behavior of water molecules at the surface of the liquid.
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for a particular redox reaction, mno2 is oxidized to mno−4 and ag is reduced to ag . complete and balance the equation for this reaction in basic solution.
The given redox reaction can be represented in the following way: MnO₂ → MnO⁴⁻ + Ag → Ag+
To balance the redox reaction, the following steps are to be followed:
1: First, balance the net ionic equation with the help of half-reactions:
MnO2 → MnO⁴⁻+ e- [Oxidation Half-Reaction]
Ag+ + e- → Ag [Reduction Half-Reaction]
2: Determine the number of electrons that are required to balance the half-reactions. The oxidation half-reaction requires five electrons.
MnO₂ → MnO⁴⁻+ 5e-
The reduction half-reaction requires one electron.
Ag+ + e- → Ag
3: Find the least common multiple of the electrons required in the half-reactions, and use it to balance the equation. The least common multiple of 5 and 1 is 5. To balance the equation, multiply the oxidation half-reaction by 1 and the reduction half-reaction by 5. This will give us the following balanced equation:
5MnO₂ + 16H₂O + Ag → 5MnO⁴⁻ + 8OH- + 4Ag+
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Are water waves transverse or longitudinal? How do you know? Own words please. No files or links either.
Answer:
Transverse waves are known by motion being perpendicular to the waves movements. Longitudinal waves move in a direction parallel to the way the wave moves. Water waves are an example of both as they move in a clockwise motion.
Explanation:
( Sorry if it is not the best answer but I did my best by researching )
How are white blood cells linked to the lymphatic system?
Answer:
The lymphatic system produces white blood cells, known as lymphocytes. There are two types of lymphocyte, T cells and B cells. They both travel through the lymphatic system. As they reach the lymph nodes, they are filtered and become activated by contact with viruses, bacteria, foreign particles, and so on in the lymph fluid.
Explanation:
A truck has a kinetic energy of 1200j and is traveling at 9 m/s what is the truck mass
Answer:
Mass of truck = 29.62 kg (Approx.)
Explanation:
Given:
Kinetic energy = 1200 J
Speed of truck = 9 m/s
Find:
Mass
Computation:
The kinetic energy of a thing is the force that has attributable to its movement in physics.
Kinetic energy = [1/2][m][v]²
1,200 = [1/2][m][9]²
1,200 = [1/2][m][81]
Mass of truck = 29.62 kg (Approx.)
If you initially have a gas with a pressure of 0.950 atm and a temperature of 35 °C and you heat it to 65 °C, what is the new pressure if volume and moles are held constant? (P2 = 1.04 atm)
Explanation:
fgIf the piston moves so as to increase the pressure of the gas to 2.94 atm, ... new volume of the cylinder? ... A gas has a pressure of 699.0 mm Hg at 40.0°C. What is the temperature (in C) ...
When the molecules in a gas lose energy the gas will turn into a liquid.
A. True
B. False
Answer:
true
Explanation:
Answer:
true
Explanation:
when the temperature of the gas is decreased or pressure on the gas is increased, the gas becomes liquid at a certain temperature or pressure.
How many moles are 2.20 x 10^25 atoms of zinc?
Please answer quick will give Brainliest!
Answer:
1.3244 x 10⁴⁹ atoms of zinc
Explanation:
2.20 x 10²⁵ moles
To convert from moles to atoms, we multiply by Avogadro's Number, 6.02 x 10²³
2.20 x 10²⁵ • 6.02 x 10²³
= 1.3244 x 10⁴⁹ atoms of zinc
Hope this helps!
How is meiosis different from mitosis
Answer:
A - meiosis results in two genetically identical offspring cell
Explanation:
Mitosis produces two diploid (2n) somatic cells that are genetically identical to each other and the original parent cell, whereas meiosis produces four haploid (n) gametes that are genetically unique from each other and the original parent (germ) cell.
Answer:
The answer is C
Explanation:
I took the test on AP3X
9. Which of the following would increase the
validity of Experiment 2?
A. Testing magnets with a volume less
than 0.04
B. Testing magnets made of iron instead
of ceramic
C. Testing generators with larger
vibrations
D. Testing a generator with coils fewer
than 2050
.
H,(8) + 1,65) - HI(g) (H = 26 kJ/mol.. Hg) + 44 1,(g) HI(g) AH=-5.0 kJ/mol... Based on the information above, what is the enthalpy change for the sublimation of iodine, represented below? 1 (s) 1,08) A. 15 kJ/mol... B 21 kJ/mol. C. 31 kJ/mol.D. 42 kJ/mol, E. 62 kJ/mol.
The enthalpy change for the sublimation of iodine I₂(s) → I₂(g) is 62 kJ/mol.
The correct answer is E: 62 kJ/mol
What is the enthalpy change for the sublimation of iodine?The enthalpy change for the sublimation of iodine (I₂) is determined using Hess's Law which states that the total enthalpy change of a reaction is independent of the pathway taken.
Given the two equations:
½ H₂(g) + ½ I₂(s) → HI(g) ΔH = 26 kJ/mol ---- (1)
½ H₂(g) + ½ I₂(g) → HI(g) ΔH = -5.0 kJ/mol ---- (2)
The equation of the sublimation of iodine is given below as follows:
I₂(s) → I₂(g)
Subtracting equation 2 from equation 1 to eliminate HI (g) gives the equation of the sublimation of iodine:
[½ H₂(g) + ½ I₂(s) → HI(g)] - [½ H₂(g) + ½ I₂(g) → HI(g)] = 26 kJ/mol - (-5.0 kJ/mol)
Simplifying:
½ I₂(s) → ½ I₂(g) ΔH = 31 kJ/mol
Multiplying the equation above by 2 gives the equation of the sublimation of iodine
I₂(s) → I₂(g) = 62 kJ/mol
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In addition to showing the ratio of atoms in a molecule, what else do the subscripts in a formula tell us?
Answer:
See explanation
Explanation:
Usually, when we write a chemical formula for any compound or other chemical specie, we use subscripts to;
Indicate the ratio of atoms of each element present in the compound or chemical specieShow the number of atoms of each element present in the compound or chemical specie.Hence, the subscripts written after chemical formulas have more than one function as described above.
In H2SO4 for instance, there are two hydrogen atoms, one sulphur atom and four oxygen atoms as shown in the chemical formula.
In the following reaction, the partial
pressure at equilibrium for each of the
products, CO and water vapor at 990°
C, is 11.0 atm and the partial pressure
for each of the reactants, H2 and CO2,
at equilibrium is 8.70 atm. What is Kp?
H2(g) + CO2(g) + H2O(g) + CO(g)
Kp = [?]
Answer:
H2+CO2=H2O+CO
Kp=(pCO)(pH2O)/(pH2)(pCO2)
= 11×11/8.70×8.70
=1.60
how can we find out the mass of the marble
In a collection of marbles, 25% of the marbles have a mass of 5.00 g and 75% of the marbles have a mass of 7.00 g. The average mass of a marble is 6.50 g.
Madison is heating two different liquids. For each liquid, she wants to compare the temperatures at which gas bubbles form, rise, and begin to escape. What physical property is Madison using to compare the liquids?Immersive Reader boiling point conductivity melting point solubility
Answer:
I think its boiling point conductivity
Answer: boiling point
Explanation:
Got it right
17. What is the molarity of ZnCl2 that forms when 15 grams of Zn reacts completely with CuCl, if a
final volume of 175 mL is produced?
Zn + CuCl2 → ZnCl2 + Cu
Answer:
1.31M
Explanation:
Based on the reaction, 1 mole of Zn produce 1 mole of ZnCl₂. As the reaction occurs completely, the moles of Zn added = Moles of ZnCl₂ produced. To find molarity we need the moles of ZnCl₂ and the volume of the solution in liters:
Moles Zn = Moles ZnCl₂ -Molar mass Zn: 65.38g/mol-:
15g * (1mol / 65.38g) = 0.23 moles of ZnCl₂
Volume in Liters:
175mL * (1L / 1000mL) = 0.175L
The molarity is:
0.23moles / 0.175L
1.31MWhich one of the following systems has the highest entropy?
10 mL of water at 100°C
10 mL of water at 50°C
10 mL of water at 10°C
Answer: a
Explanation:
The highest entropy will be 0 mL of water at 100°C.
What is entropy?Entropy is just a measured physical quality that will be most usually linked with disorder, unpredictability, or uncertainty.
The quantity of random movement in a system increases as more energy is put into it. Entropy rises like a volume increases in a system.
Therefore, the correct answer will be option 1.
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predict the charge on the predominant species of the peptide e−d−k−r−a−s−t at ph 5.0 .
At pH 5.0, the predominant species of the peptide E-D-K-R-A-S-T has a net positive charge of +2.
To predict the charge on the predominant species of the peptide E-D-K-R-A-S-T at pH 5.0, we need to consider the pKa values of the amino acids involved and the pH of the solution. The pKa values represent the acidity or basicity of the functional groups present in the amino acids.
1. At pH 5.0, the carboxyl group of glutamic acid (E) and aspartic acid (D) will be protonated, resulting in a positive charge on these amino acids. So, E and D will have a positive charge.
2. Lysine (K), arginine (R), histidine (H), and the N-terminus of the peptide have amino groups that can act as bases. At pH 5.0, these amino groups will be protonated, resulting in a positive charge on K, R, H, and the N-terminus.
3. Threonine (T), serine (S), and the C-terminus of the peptide do not have ionizable groups at pH 5.0 and will remain uncharged.
Therefore, at pH 5.0, the predominant species of the peptide E-D-K-R-A-S-T will have a net positive charge due to the protonation of E, D, K, R, H, and the N-terminus. The charge can be represented as follows:
E-D-K-R-A-S-T (at pH 5.0): 2+
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Gerald's science teacher mixed liquid X and liquid Y, both at room-temperature, in a large beaker. two beakers of clear solutions to the left of a right-pointed arrow, and a large beaker with a clear solution to the right of the arrow The mixture in the large beaker still looked clear like water, but when the students, one at a time, carefully touched the outside of the large beaker, it felt warm to the touch. Why did the large beaker most likely feel warm? A. The two liquids were not soluble in water. B. The release of a gas heated the solution. C. A chemical reaction produced a new substance. D. The energy of mixing warmed the liquids.
Answer:
c
Explanation:
A chemical reaction produced a new substance. In a chemical reaction, the atoms that make up the reactants are rearranged to produce various products.
What is chemical reaction?chemical reaction, the transformation of one or more chemicals (the reactants) into one or more distinct compounds (the products). Chemical elements or chemical compounds make up substances.
A chemical reaction is one in which two or more reactants will react to form a new substance. When new substance will form it will produce heat. Therefore, when science teacher was mixing two liquids it was generating heat.
Heating a substance allow molecules to move faster. When heat is given to the object it will move fast. When heat will apply to a solid it will turn into liquid. When heat is supplied to the liquid it will turn into gas.
Therefore, A chemical reaction produced a new substance. In a chemical reaction, the atoms that make up the reactants are rearranged to produce various products.
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How many molecules are there in 24 grams of HSO₃?
Answer it right for a brainliest
Answer:
plz I. need a brainliest
Explanation:
I hope you have a good day
Do noble gases form bonds? Why or why not?
◕‿↼ Hey There!
Answer → Source Noble Gases have a full valence shell, which is why they rarely form bonds with other atoms.
✨ Hope This Helps!✨