Explanation:
n=m/M
m=n*M
m=5,09 mol * 54,9g/mol
m= 279,4g
[tex]\text{mass of Mn = 5.09 mol Mn} × \frac{\text{54.94 g Mn}}{\text{1 mol Mn}}[/tex]
[tex]\boxed{\text{mass of Mn = 279.6 g}}[/tex]
What is the pH of a neutral solution at 25ºC?
a. 14
b. 0
c. 1
d. 7
Answer:
d.7 is the correct answer
Match each definition to the appropriate term.
a. The condition that a reaction takes place without outside help _________
b. Difference of the enthalpy (of a system) minus the product of the entropy and absolute temperature ________
c. Sum of the internal energy plus the product of the pressure and volume for a reaction _________
d. The extent of randomness in a system __________
e. Solution in which no more solute can be dissolved in the solven ________
1. Gibbs free energy
2. Spontaneity
3. Saturated solution
4. Entropy
5. Enthalpy
Answer:
a. The condition that a reaction takes place without outside help Spontaneity
b. Difference of the enthalpy (of a system) minus the product of the entropy and absolute temperature Gibbs free energy
c. Sum of the internal energy plus the product of the pressure and volume for a reaction Enthalpy.
d. The extent of randomness in a system Entropy
e. Solution in which no more solute can be dissolved in the solven Saturated solution
Explanation:
(a) SPONTANEITY - The quality of being natural rather than planned in advance is described as spontaneity.
(b) GIBBS FREE ENERGY - Gibbs free energy, also known as the Gibbs function, Gibbs energy, or free enthalpy, is a quantity used to quantify the maximum amount of work that can be performed in a thermodynamic system when the temperature and pressure are held constant. The symbol ‘G' stands for Gibbs free energy.
(c) ENTHALPY - The heat absorbed or released during a process at constant pressure is equal to the Enthalpy shift. While “enthalpy” is often referred to as “heat content,” most people prefer to refer to it as “enthalpy.”
(d) ENTROPY - Entropy is the amount of thermal energy in a device per unit temperature that can't be used to do useful work. Since work is produced by ordered molecular motion, entropy is also a measure of a system's molecular disorder, or randomness. For several everyday phenomena, the idea of entropy offers profound insight into the direction of spontaneous change.
(e) SATURATED SOLUTION - A saturated solution is a chemical solution that contains the maximum amount of dissolved solute in the solvent. In a saturated solution, the extra solute will not dissolve. A number of factors influence the amount of solute that can be dissolved in a solvent to form a saturated solution.
The following solutions are prepared by dissolving the requisite amount of solute in water to obtain the desired concentrations. Rank the solutions according to their respective osmotic pressures in decreasing order assuming the complete dissociation of ionic compounds. Rank from highest to lowest osmotic pressure. To rank items as equivalent, overlap them.
A. 1 M MgCl2
B. 1 M KCI
C. 1 M C12
D. H22011
1. Highest osmotic pressure
2. Lowest osmotic pressure
Answer: 1. Highest osmotic pressure : 1 M [tex]MgCl_2[/tex]
2. Lowest osmotic pressure: 1 M [tex]C_{12}H_{22}O_{11}[/tex]
Explanation:
[tex]\pi=i\times C\times R\times T[/tex]
[tex]\pi[/tex]= osmotic pressure
i = Van'T Hoff factor
C = concentration
T = Temperature
1. For 1M [tex]MgCl_2[/tex]
, i= 3 as it is a electrolyte and dissociate to give 3 ions.
[tex]MgCl_2\rightarrow Mg^{2+}+2Cl^{-}[/tex]
2. For 1 M [tex]KCl[/tex]
, i= 2 as it is a electrolyte and dissociate to give 2 ions.
[tex]KCl\rightarrow K^{+}+Cl^{-}[/tex]
3. For 1M [tex]C_{12}H_{22}O_{11}[/tex]
, i= 1 as it is a non electrolyte and do not dissociate.
Thus as vant hoff factor is highest for [tex]MgCl_2[/tex] thus osmotic pressure is highest for 1 M [tex]MgCl_2[/tex]
And as vant hoff factor is lowest for [tex]C_{12}H_{22}O_{11}[/tex] thus osmotic pressure is lowest for 1 M [tex]C_{12}H_{22}O_{11}[/tex]
Methane and sulfur react to produce carbon disulfide (CS₂), a liquid often used in the production of cellophane.
2CH₄ + S₈ --> 2CS₂ + 4H₂S
Calculate the moles of H₂S produced when 2.25 mol S₈ is used.
Answer:
9 moles
Explanation:
The balanced chemical equation provided in this question is as follows:
2CH₄ + S₈ → 2CS₂ + 4H₂S
In accordance to the above balanced equation, 1 mole of sulphur (S8) produces 4 moles of hydrogen sulfide (H2S).
Therefore, if 2.25mol of S8 is used, 2.25 × 4 = 9 mol
9 moles of H2S is produced.
how many atoms of carbon are in a diamond with a mass of 0.568 g?
Answer:
There are 2.85 x 10^22 atoms of carbon in a diamond with a mass of 0.568 g.
Hope this helps! :)
Is c6h4cl2 soluble in water?
Answer:
slightly but poorly
Explanation:
it is a white crystalline solid that is practically insoluble in water and soluble in ether, chloroform, carbon disulfide, benzene, alcohol and acetone.
You are given 19.2 liters of H3PO4. How many moles do you have?
Answer:
Explanation:
Do a quick conversion: 1 grams H3PO4 = 0.010204583427424 mole using the molecular. How many grams H3PO4 in 1 mol? You can view more details on each measurement unit: molecular weight of H3PO4 or mol This. The formula weight is simply the weight in atomic mass units of all the atoms in a given formula.
What is the final molarity of a solution when 250 mL H2O is added to 150 mL
0,040 M NaOH(aq)?
Answer:
0.015M is the final molarity of the NaOH solution
Explanation:
A solution of 0.040M NaOH is diluted from 150mL to 250mL + 150mL = 400mL. That means the solution is diluted:
400mL / 150mL = 2.667 times.
As the original solution has a concentration of 0.040M, the diluted solution has a concentration of:
0.040M / 2.667 =
0.015M is the final molarity of the NaOH solutionHow many oxygen atoms are in 3.30 g of quartz?
Answer:
3.30 gSiO2 / 60.085g SiO2 x 2 mol 0 / 1 mol SiO2 x (6.022*1023 ) = 6.61*1022 O atoms
Explanation:
b) Name three substances which can undergo sublimation and deposition respectively
solid carbon dioxide, iodine, arsenic, and naphthalene
Explanation:
Examples of substances that undergo sublimation
Examples of solids that sublime are dry ice (solid carbon dioxide), iodine, arsenic, and naphthalene (the stuff mothballs are made of).
17. The equation below represents a chemical reaction that occurs in living cells.
CoH1206 + 602 -- 6002 + 6H20 + energy
How many atoms are represented in the reactants of this equation?
Answer:
36 atoms
Explanation:
C₆H₁₂O₆ + 6O₂ → 6CO₂ + 6H₂O + energyThe reactants are in the left side of the equation. First we determine how many atoms are there in the C₆H₁₂O₆ molecule:
6 C atoms + 12 H atoms + 6 O atoms = 24 atoms in totalThere are two atoms in a O₂ molecule, and there are 6 O₂ molecules in the equation:
2 * (6 O atoms) = 12 atoms in totalThe total number of atoms in the reactants is
24 + 12 = 36 atomsA mixture of 65 percent N2 and 35 percent CO2 gases (on a mass basis) enters the nozzle of a turbojet engine at 60 psia and 1400 R with a low velocity, and it expands to a pressure of 12 psia. If the isentropic efficiency of the nozzle is 88 percent, determine:
(a) the exit temperature
(b) the exit velocity of the mixture.
Assume constant specific heats at room temperature.
Answer:
a. 969.1 R
b. 2237 ft/s
Explanation:
First the apparent specific heats are determined from the mass fractions of the gases:
[tex]c_{p} &=\left(\mathrm{mf} c_{p}\right)_{\mathrm{N}_{2}}+\left(\mathrm{mf} c_{p}\right) \mathrm{CO}_{2} \\ &=(0.65 \cdot 0.248+0.35 \cdot 0.203) \frac{\mathrm{Btu}}{\mathrm{lbm} \mathrm{R}} \\ &=0.232 \frac{\mathrm{Btu}}{\mathrm{lbmR}} \\ c_{v} &=\left(\mathrm{mf} c_{v}\right)_{\mathrm{N}_{2}}+\left(\mathrm{mf} c_{v}\right)_{\mathrm{CO}_{2}} \\ &=(0.65 \cdot 0.177+0.35 \cdot 0.158) \frac{\mathrm{Btu}}{\mathrm{lbmR}} \\ &=0.170 \frac{\mathrm{Btu}}{\mathrm{lbmR}}[/tex]
The isentropic coefficient then is:
[tex]k &=\frac{c_{p}}{c_{v}} \\ &=\frac{0.232}{0.17} \\ &=1.365[/tex]
The final temperature is determined from the isentropic nozzle efficiency relation:
[tex]T_{2} &=T_{1}-\eta_{N}\left(T_{1}-T_{2 s}\right) \\ &=T_{1}\left(1-\eta_{N}\left(1-\left(\frac{P_{2}}{P_{1}}\right)^{(k-1) / k}\right)\right) \\ &=1400\left(1-0.88\left(1-\left(\frac{800}{100}\right)^{(1.365-1) / 1.365}\right)\right) \mathrm{R} \\ &=969.1 \mathrm{R}[/tex]
b. The outlet velocity is determined from the energy balance:
[tex]h_{1} &+\frac{v_{1}^{2}}{2}=h_{2}+\frac{v_{2}^{2}}{2} \\ v_{2} &=\sqrt{2 c_{p}\left(T_{1}-T_{2}\right)} \\ &=\sqrt{2 \cdot 0.232(1400-969.2) \cdot 25037} \frac{\mathrm{ft}}{\mathrm{s}} \\ &=2237 \frac{\mathrm{ft}}{\mathrm{s}}[/tex]
Calculate the pH for the following weak acids
.01M Formic acid (HCHO2) aka= 1.7 x 10^-4
Answer:
pH = 2.88
Explanation:
For a weak acid solution, the pH can be calculated using the following formulas:
[H⁺] = [tex]\sqrt{Ka*C}[/tex]pH = -log[H⁺]Where Ka = [tex]10^{-pKa}[/tex] and C is the molar concentration.
We are given Ka and C by the problem, meaning we can now proceed to calculate [H⁺]:
[H⁺] = [tex]\sqrt{1.7*10^{-4}*0.01}[/tex] [H⁺] = 0.0013 MFinally we calculate the pH:
pH = - log (0.0013) = 2.88What is created when an acid is mixed with a base?
Answer:
If you mix equal amounts of a strong acid and a strong base, the two chemicals essentially cancel each other out and produce a salt and water. Mixing equal amounts of a strong acid with a strong base also produces a neutral pH (pH = 7) solution.
Ms. Fremont spent last weekend grading tests . If she spent 4 min on each test , how many hours did it take her to grade all 74 tests ?
Answer:
about 5 hours
Explanation:
When doing this problem you mmust mulitiply 4 x 74 and divide the answer by 60 because 60=1 hour.
What happened during the fusion reaction shown? 2H Зн 4He neutron O A. Two H nuclei fused into one He nucleus. O B. One He nucleus split into two H nuclei. O C. The nuclei that fused lost all their neutrons. D. The nuclei that fused lost some of their protons.
Answer: C.
Explanation:
two H nuclei fused into one He nucleus
Answer: A!
Explanation: just did it
How is gravity an attractive force?
LEVEL 3
Write the correct order
of letters to the finish line.
A E B E C
Example:
ABCGH
G
H
N
eza
Not correct
plz, help me I'm so confused!
(this is also science)
Answer:
Well, there is no photo...
Explanation:
A dunk tank holds 550,200 grams of water. How many moles of water are in the tank?
Answer:
Aà bhûtÿ ñhjkjłfd hÿrèërqw
Explanation:
Please help with yes or no
How many grams (g) are in 4.00 moles of Carbon (C) ?
Answer:
There are 36 grams in 4.00 moles of Carbon.
Explanation:
In order to convert from moles of a substance into grams of the same substance, we need to use the substance's molar mass.
That means that in this case we use the molar mass of Carbon:
4.00 mol * 12 g/mol = 36 gThus, there are 36 grams in 4.00 moles of Carbon.
Select the correct answer.
For Al, its atomic number is 13 and its mass number is 27. How many neutrons does it have?
Ο Α. .
13
ОВ.
14
26
OD
27
O E
40
Answer:
B.) 14
Explanation:
27-13=14 neutrons
What is the coefficient for hydrogen in the balanced equation for the reaction of solid tungsten(VI) oxide with gaseous hydrogen to form solid tungsten and liquid water?
Answer:
2
Explanation:
WO2(s) + 2H2(g) -> W(s) + 2H2O(l)
PLEASE HELPPP WILL GIVE 10 PTS AND MARK BRAINIEST TO RIGHT ANSER!!!!!
Roasted coffee beans contain over_____________ chemical compounds
A) 10000000
B) 1000000
C) 1000
D) 10000
Answer:
C. 1000
l think this is correct answer
l hope it's helpful for you
What class of chemicals is responsible for ozone depletion?
Which expression represents the concentration of OH– in solution?
a. 10–14 / [H3O+]
b. [OH–] / 10–14
c. 10–14 – [H3O+]
d. 10–14 x [H3O+]
In an electrical circuit, the presence of a resistor limits the current and prevents
damage related to short circuits.
True or
False
Help me! Who ever gets to answer and has the best answer gets brainliest (very easy!)
Answer:
Fires --> These consume fuel and convert chemical energy stored in that fuel into thermal light and sound energy.
Decay -->The breakdown of dead plants and animals releases thermal energy.
Earth --> Thermal energy comes from deep inside and it is called geothermal energy.
bond. Water is a polar solvent. The oxygen atom, being more electronegative, attracts the electron cloud toward itself. As the electron cloud is pulled by the oxygen atom, it carries a partial negative charge, and the hydrogen atoms carry a partial positive charge. This partial separation of charges in the water molecule makes it polar. Which intermolecular forces contribute to the dissolution of NaCl in water
Answer:
NaCl and water: Ion - Dipolo forces
NaCl and Hexane: Ion-ion force between Na+ and Cl− ions and London dispersion force between two hexane molecules
Explanation:
NaCl and water:
The ion-dipole force is established between an ion and a polar molecule. Polar molecules are dipoles, they have a positive end and a negative end.
H2O has an important charge separation in its atoms (the H has a positive partial charge and the O has a negative partial charge) and this causes permanent electrical dipoles in the water molecules.
Sodium chloride is an ionic compound formed of positive and negative charge ions, Na + and Cl-. Depending on their charge, these ions will be attracted to opposite charges in the water molecules (H attracts chloride ions and O attracts sodium ions), causing the salt to dissolve in water.
Explanation: