make a 450 gram solution with the mass by mass concentration of 7% how much salt and water do you need to mix
What is the pH of a 1.0 x 10-3 M KOH solution?
A. 10
B. 4.0
C. 11
D. 3.0
Answer:
Option C. 11
Explanation:
We'll begin by calculating the concentration of the hydroxide ion [OH¯] in the solution. This can be obtained as follow:
In solution, KOH will dissociate as follow:
KOH (aq) <=> K⁺(aq) + OH¯(aq)
From the balanced equation above,
1 mole of KOH reacted to produce 1 mole of OH¯.
Therefore, 1×10¯³ M KOH will also react to produce 1×10¯³ M OH¯.
Thus, the concentration of hydroxide ion [OH¯] in the solution is 1×10¯³ M
Next, we shall determine the pOH of the solution. This can be obtained as follow:
Concentration of hydroxide ion [OH¯] = 1×10¯³ M
pOH =?
pOH = –Log [OH¯]
pOH = –Log 1×10¯³
pOH = 3
Finally, we shall determine the pH of the solution. This can be obtained as follow:
pOH = 3
pH =?
pH + pOH = 14
pH + 3 = 14
Collect like terms
pH = 14 – 3
pH = 11
draw the structure of iso -pentylpropanoate
If 30.0 grams of AlC3 is produced in the reaction, how many grams of HCI must have reacted?
Answer:
Al2O3 + 6HCl ==> 2AlCl3 + 3H2O ... balanced equation
moles Al2O3 present = 30.0 g x 1 mol/101.96 g = 0.294 moles
moles HCl present = 30 g HCl x 1 mol/36.5 g = 0.822 moles HCl
HCl is LIMITING as it takes 6 moles HCl for each 1 mol Al2O3 and here that is not enough. It will run out first.
Now, using the limiting reactant, we find the moles and mass of AlCl3 that can be formed.
0.822 moles HCl x 2 moles AlCl3/6 moles HCl = 0.274 moles AlCl3 formed
mass of AlCl3 = 0.274 moles AlCl3 x 133 g/mole = 36.4 g AlCl3 formed
What is pH value in simple words?
How does kinetic energy transform into potential energy?
TIMED HELP ASAP
19.11 g of MgSO₄ is placed into 100.0 mL of water. The water's temperature increases by 6.70°C. Calculate ∆H, in kJ/mol, for the dissolution of MgSO₄. (The specific heat of water is 4.184 J/g･°C and the density of the water is 1.00 g/mL). You can assume that the specific heat of the solution is the same as that of water.
Answer:
TIMED HELP ASAP
19.11 g of MgSO₄ is placed into 100.0 mL of water. The water's temperature increases by 6.70°C. Calculate ∆H, in kJ/mol, for the dissolution of MgSO₄. (The specific heat of water is 4.184 J/g･°C and the density of the water is 1.00 g/mL). You can assume that the specific heat of the solution is the same as that of water.
Answer:
-21.03 kJ/mol
Explanation:
∆H is enthalpy. Enthalpy is the total heat content of a system.
So we can establish that ∆H = q (heat)
The formula for heat (q)
q = cm∆T
c = specific heat capacity
m = mass of substance
∆T= change of temperature
Since we are calculating the enthalpy of the SOLUTION. We must account for both the mass of water and the mass of MgSO₄ in our q formula.
All you gotta do is plug and chug at this stage.
∆H = q = cm∆T = (4.184)(19.11+100.0)(6.70) = 3338.986808 Joules
We have now calculated the heat (aka enthalpy) of the solution.
BUT
Remember! The problem asked for enthalpy in kj....
Use this conversion factor.
1000 J = 1 kJ
3338.986808 Joules * 1kJ/1000 J = 3.338986808 kJ
We were asked to find ∆H for the dissolution of MgSO4 in units of kj/mol so we are not finished.
Take the grams of MgSO4 in the problem and convert it into moles using its molar mass.
MgSO4 molar mass = 120.3676 g
1 mol = 120.3676 g MgSO4 <---- Use this as a conversion factor
19.11 g MgSO4 * 1 mol MgSO4/120.3676 g = 0.15876365 mol MgSO4
Now that you've calculated the moles of MgSO4 in this solution. You can divide your heat by it.
q dissolution = 3.338.986808 kJ/ 0.15876365 mol = 21.03 kj/mol
Note that the problem tells us that the temperature of water increases.
This means that the water is experiencing an endothermic process (heat is being absorbed from MgSO4) . Mathematically, this would be indicated by a positive sign. ---> +q
We can assume MgSO4 is losing heat as it is placed into the water. It is experiencing an exothermic process (heat is being lost). Mathematically, this would be indicated by a negative sign. ----> -q
So if we're calculating the enthalpy for the dissolution of MgSO₄ ....the value we've arrived at must be negative.
Answer
∆H = 21.03 kj/mol :)))))
I hope that helped...I feel like my explanation was a bit convoluted.
Is this population more likely to grows slowly or quickly in the next 10 years
nobody can say it is uncertain but in my opinion it will grow quickly in the next 10 years
Name each compound. Do not capitalize element names. An example can be seen
below.
Ex. SF6: sulfur hexfluoride
a. H2O:
b. PC15:
C. SiF4:
d. N20
Answer:
a. H2O: dihydrogen monoxide
b. PCl5: Phosphorus pentachloride
c. SiF4: Silicon tetrafluoride
d. N20: dinitrogen oxide
option with explaination
Answer:
B. it's water of crystallization.
the water of crystallization, that is the number of molecules of water attached to One Copper atom gives blue color to the hydrated salt (CuSO4.5H2O)
nguyên tử sắt có điện tích hạt nhân là 26+. trong nguyên tử, số hạt mang điện nhiều hơn số hạt không mang điện là 22. Hãy xác định số khối của nguyên tử sắt
Answer:
I don't know yr language
Calculate the molar mass AND identify the gas if 3.25 kg of this gas is stored in a 15.00 L tank and exerts a pressure of 120.0 atm at a constant temperature of 66.0°C.
Answer:
is your question correct
.
..
.
.
.
or not
How many grams of hydrogen is produced from 12.5 G of MG reacting with hydrochloric acid in this balanced equation?
Mg+ 2HCL —>MgCl2+H2
Answer:
1.03 grams of hydrogen is produced from 12.5 g of Mg reacting with hydrochloric acid.
Explanation:
The balanced reaction is:
Mg+ 2 HCl → MgCl₂ + H₂
By stoichiometry of the reaction, the following amounts of moles of each compound participate in the reaction:
Mg: 1 moleHCl: 2 molesMgCl₂: 1 moleH₂: 1 moleBeing the molar mass of each compound:
Mg: 24.31 g/moleHCl: 36.45 g/moleMgCl₂: 95.21 g/moleH₂: 2 g/moleBy reaction stoichiometry, the following mass amounts of each compound participate in the reaction:
Mg: 1 mole* 24.31 g/mole= 24.31 gHCl: 2 moles* 36.45 g/mole= 72.9 gMgCl₂: 1 mole* 95.21 g/mole= 95.21 gH₂: 1 mole* 2 g/mole= 2 gThen you can apply the following rule of three: if by stoichiometry 24.31 grams of Mg produces 2 grams of H₂, 12.5 grams of Mg produces how much mass of H₂?
[tex]mass of H_{2} =\frac{12.5 grams of Mg* 2 grams of H_{2}}{24.31 grams of Mg}[/tex]
mass of H₂= 1.03 grams
1.03 grams of hydrogen is produced from 12.5 g of Mg reacting with hydrochloric acid.
Indicar que elemento es de transición *
a) Calcio
b) Radio
c) Hierro
d) Carbono
e) Azufre
Sabiendo que las configuraciones electrónicas son correctas, determinar qué analogía es incorrecta *
a) 47Ag: [Kr] 5s2 4d9 I – B
b) 27Co: [Ar] 4s2 3d7 VIII – B
c) 41Nb: [Kr] 5s2 4d3 V – A
d) 50Sn: [Kr] 5s2 4d10 5p2 IV – A
e) N.A.
porfaaaaaaaaaaaaaaaaaaaa
Answer:
c hierro
no se la otra sorry
copper II carbonate in a crucible produced only 7g of copper II oxide. What was the percentage yield of copper II oxide
The question is incomplete, the complete question is;
.On heating 12.4 g of copper (II) carbonate in a crucible only 7.0g of copper (II) oxide was produced. What was the % yield of copper (II) oxide ? [Cu=64,C=12,O=16]
Answer:
87.5%
Explanation:
CuCO3 -------> CuO + CO2
Number of moles of CuCO3 = 12.4g/123.55 g/mol = 0.1 moles
Since the reaction is 1:1,
Mass of CuO produced = 0.1 moles × 80g/mol = 8 g
Hence,
% yield = actual yield/theoretical yield × 100
% yield = 7/8 × 100
% yield = 87.5%
Which element has 2 valence electrons in the 2s sublevel?
Answer:
beryllium is the answer.
I hope this will help you
what are the intermolecular forces of Sulfate ion
Answer:
oh it's easy
Explanation:
Take the hydrate
N
a
2
S
2
O
3
∙
5
H
2
O
. Are there ionic forces between the
N
a
+
and the
S
2
O
2
−
3
and ion-dipole forces between the cation/anions and the water?
PLEASE HELP QUICK!!! How many molecules are there in 4.00 L of
glucose, C6H1206? Please show your work!!
Which diagram represents this molecule
Answer:
I think it is C
Explanation:
Hope this helps!! :)
If I'm wrong, then greatest apologies
What does this chemical energy reaction describe? Water-hydrogen+oxygen
Answer:
may be you mean water= hydrogen + oxygen, this reaction describes that water is made by the combination of hydrogen and oxygen.
PLZ HELP According to the atomic model Which particles are found In the same part of the atom
a. protons electrons neutrons
B.protons and neutrons
C.protons and electrons
D.electrons and neutrons
how much energy is required to melt 2kg of aluminium
what is transition state
Answer:
transition state is a point in which electrons been removed from the atom
Answer:
The highest energy structure in the reaction coordinate.
Explanation:
Exprese la concentración de una solución de H3PO4 al 30 % en masa y con una densidad de 1.39 g/mL en: M, y N.
Respuesta:
4.26 M; 12.8 N
Explicación:
Primer paso: Calcular la concentración volumétrica (Cv)
Usaremos la siguiente expression.
Cv = Cg × ρ
Cv = 30 g%g × 1.39 g/mL = 41.7 g%mL
Segundo paso: Calcular la molaridad
La concentración volumetrica es 41.7 g%mL, es decir, hay 41.7 gramos de soluto cada 100 mL de solución. Usaremos la siguiente fórmula para molaridad.
M = masa de soluto / masa molar de soluto × litros de solución
M = 41.7 g / 97.99 g/mol × 0.1 L = 4.26 M
Tercer paso: Calcular la normalidad
Usaremos la siguiente fórmula.
N = M × Z
donde Z para un ácido es igual al número de protones.
N = M × Z
N = 4.26 mol/L × 3 eq/mol = 12.8 N
Anyone please help I’m in summer school please
Answer:
1. Absolute time, also known as Newtonian time is a time that exists independent of the observer of the time, and therefore, can only be expressed through mathematics
Absolute dating is a dating method that makes use of the radioactive property of matter and is determined through dating of radioactive isotopes present
Absolute time (dating) is found through radioactive dating
2. Radioactive isotopes are atoms that have the property of unstable proton neutron combination or excess energy nucleus. They can be fined as unstable element
3. A stabilized isotope are the decay product atoms of the element which are non radioactive.
4. The half life is the time it takes the original isotope to decay into the decay product
5. To determine the age of a rock, the proportion of the original isotope to the amount of decay product in the rock is compared
6. The isotope used to date organic materials is carbon-14
7. The isotope used to date rocks with comparable age to the Earth is Uranium-238 that has a half life of 4.468 billion years
8. The half life of carbon-14 is only 5,700 years while the age of a dinosaur is between 245 and 66 million years ago, and therefore, carbon is absent in most fossils
9. Uranium-238 is only found in igneous or volcanic rocks and not in metamorphic rocks, therefore, fossils of dinosaur as well as other fossils that are buried in sedimentary materials, including sand and clay, cannot be determined by Uranium-238
Explanation:
How are the vapor pressure and boiling point of alkynes affected as the chain length increases?
Answer:
Answer to the following question is as follows;
Explanation:
Alkynes' vapour pressure and normal boiling points are altered when chain length grows, since vapour pressure rises while boiling point falls.
Vapour pressure always include pressure entered by vapour with its condensed phase, pressure include molecules force of attraction include vapour
What is the total pressure in millimeters of mercury,
exerted by the gas mixture
P= _______ units?
Answer:
87059.50558 pa
Explanation:
Dalton's law of partial pressure states that Ptotal=P1 +P2+ P3
417mmHg + 150mmHg +86mmHg =653 mmHg
convert it to Pa, your answer is 87059.50558Pa.
I hope I'm of help to you
is SrO a conductor of electricity
Answer:
No and Yes
Explanation:
it depends bc its an ionic compound, therefore can't conduct electricity when SOLID, BUT unless it DISSOLVES in water it can conduct
Is FeS iron (ll) sulfide or iron (lll) sulfide?
Answer:
the valence of S is -2. For FeS to be neutral the valence of Fe used must be +2
and since Iron (II) has its valency 2, FeS will be Iron (II) Sulfide.
NaC2H3O2 product or reactant
Answer:
the reaction between vinegar and baking soda, the reactants are vinegar (acetic acid) and baking soda (sodium bicarbonate). The products are sodium acetate, water, and carbon dioxide gas.
