Transition elements or transition metals is sometimes used to refer to the entire set of d block elements
Transition elements are components to partially filled d orbitals (also recognised as transition metals). Transition structures are identified by IUPAC as elements with such a partially filled d subshell or elements able to form stable cations with an imperfectly packed d orbital. Transition metals are factors present in the periodic table between both the s-block and the p-block. As a result, they are made reference to as d-block elements. Transition metals are unsteady metals with transition phase behaviour between both the s and p block elements, hence their name.
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Which of the following may add salt to ocean waters?
volcanic eruptions
melting glaciers
rain
biological precipitation
Answer:
rain
Explanation:
The volcanic eruptions may add salt to ocean waters. option A is correct.
What is a volcanic eruption?
Volcanic eruption produces or releases direct minerals into the water or in the ocean and salt domes are also responsible to increase the salt concentration in the water.
Two of the most commonly found ions in the water of oceans are chloride ions and sodium ions. 85% of the concentration found remaining are the magnesium and sulfate salts.
This process also happens with the mountains but in oceans it invertases the concentration of salt.
Therefore, volcanic eruptions may add salt to ocean waters. option A is correct.
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The lobes are important for speech and language. O A. parietal O B. temporal o o Ο Ο C. frontal O D. occipital
Answer:
Explanation:
D or b
Sorry if wrong
Answer:
temporal
Explanation:
A 50.0 mL solution of 0.129 M KOH is titrated with 0.258 M HCl. Calculate the pH of the solution after the addition of each of the given amounts of HCl.
A) 0.00ml
B)7.00ml
C)12.5ml
D)18.0ml
E)24.0ml
F)25.0ml
G)26.0ml
H)29.0ml
please show work with steps .
Answer:
A- pH = 13.12
B- pH = 12.91
C- pH = 12.71
D- pH = 12.43
E- pH = 11.55
F- pH = 7
G- pH = 2.46
H- pH = 1.88
Explanation:
This is a titration of a strong base with a strong acid. The neutralization reaction is: KOH (aq) + HCl (aq) → H₂O(l) + KCl(aq)
Our pH at the equivalence point is 7, because we have made a neutral salt.
To determine the volume at that point we state the formula for titration:
mmoles of base = mmoles of acid
Volume of base . M of base = Volume of acid . M of acid
50mL . 0.129M = 0.258 M . Volume of acid
Volume of acid = (50mL . 0.129M) / 0.258 M → 25 mL (Point F)
When we add 25 mL of HCl, our pH will be 7.
A- At 0 mL of acid, we only have base.
KOH → K⁺ + OH⁻
[OH⁻] = 0.129 M
To make more easy the operations we will use, mmol.
mol . 1000 = mmoles → mmoles / mL = M
- log 0.129 = 0.889
14 - 0.889 = 13.12
B- In this case we are adding, (7 mL . 0.258M) = 1.81 mmoles of H⁺
Initially we have 0.129 M . 50 mL = 6.45 mmoles of OH⁻
1.81 mmoles of H⁺ will neutralize, the 6.45 mmoles of OH⁻ so:
6.45 mmol - 1.81 = 4.64 mmoles of OH⁻
This mmoles of OH⁻ are not at 50 mL anymore, because our volume has changed. (Now, we have 50 mL of base + 7 mL of acid) = 57 mL of total volume.
[OH⁻] = 4.64 mmoles / 57 mL = 0.0815 M
- log 0.0815 M = 1.09 → pOH
pH = 14 - pOH → 14 - 1.09 = 12.91
C- In this case we add (12.5 mL . 0.258M) = 3.22 mmoles of H⁺
Our initial mmoles of OH⁻ would not change through all the titration.
Then 6.45 mmoles of OH⁻ are neutralized by 3.22 mmoles of H⁺.
6.45 mmoles of OH⁻ - 3.22 mmoles of H⁺ = 3.23 mmoles of OH⁻
Total volume is: 50 mL of base + 12.5 mL = 62.5 mL
[OH⁻] = 3.23 mmol / 62.5 mL = 0.0517 M
- log 0.0517 = 1.29 → pOH
14 - 1.11 = 12.71
D- We add (18 mL . 0.258M) = 4.64 mmoles of H⁺
6.45 mmoles of OH⁻ are neutralized by 4.64 mmoles of H⁺.
6.45 mmoles of OH⁻ - 4.64 mmoles of H⁺ = 1.81 mmoles of OH⁻
Total volume is: 50 mL of base + 18 mL = 68 mL
[OH⁻] = 1.81 mmol / 68 mL = 0.0265 M
- log 0.0265 = 1.57 → pOH
14 - 1.57 = 12.43
E- We add (24 mL . 0.258M) = 6.19 mmoles of H⁺
6.45 mmoles of OH⁻ are neutralized by 6.19 mmoles of H⁺.
6.45 mmoles of OH⁻ - 6.19 mmoles of H⁺ = 0.26 mmoles of OH⁻
Total volume is: 50 mL of base + 24 mL = 74 mL
[OH⁻] = 0.26 mmol / 74 mL = 3.51×10⁻³ M
- log 3.51×10⁻³ = 2.45 → pOH
14 - 2.45 = 11.55
F- This the equivalence point.
mmoles of OH⁻ = mmoles of H⁺
We add (25 mL . 0.258M) = 6.45 mmoles of H⁺
All the OH⁻ are neutralized.
OH⁻ + H⁺ ⇄ H₂O Kw
[OH⁻] = √1×10⁻¹⁴ → 1×10⁻⁷ → pOH = 7
pH → 14 - 7 = 7
G- In this case we have an excess of H⁻
We add (26 mL . 0.258M ) = 6.71 mmoles of H⁺
We neutralized all the OH⁻ but some H⁺ remain after the equilibrium
6.71 mmoles of H⁺ - 6.45 mmoles of OH⁻ = 0.26 mmoles of H⁺
[H⁺] = 0.26 mmol / Total volume
Total volume is: 50 mL + 26 mL → 76 mL
[H⁺] = 0.26 mmol / 76 mL → 3.42×10⁻³ M
- log 3.42×10⁻³ = 2.46 → pH
H- Now we add (29 mL . 0.258M) = 7.48 mmoles of H⁺
We neutralized all the OH⁻ but some H⁺ remain after the equilibrium
7.48 mmoles of H⁺ - 6.45 mmoles of OH⁻ = 1.03 mmoles of protons
Total volume is 50 mL + 29 mL = 79 mL
[H⁺] = 1.03 mmol / 79 mL → 0.0130 M
- log 0.0130 = 1.88 → pH
After equivalence point, pH will be totally acid, because we always have an excess of protons. Before the equivalence point, pH is basic, because we still have OH⁻ and these hydroxides, will be neutralized through the titration, as we add acid.
The pH value is given by 14 less the logarithm of the hydronium ion
concentration or the hydrogen ion concentration in the solution.
Responses (approximate values):
The pH values are;
A) 13.11
B) 12.91
C) 12.71
D) 12.42
E) 11.54
F) 7
G) 2.469
H) 1.884
Which is used to find the pH of the solution?A) Concentration of the KOH = 0.129 M
Amount of HCl added = 0.00 ml
The pH = -log[H⁺] = 14 - pOH
pOH = -log[OH⁻]
Which gives;
pH = 14 - (-log[OH⁻] )
pH = 14 - (-log(0.129)) ≈ 13.11B) Volume of acid added = 7.00 mL = 0.007 L
Concentration of the acid = 0.258 M HCl
Number of moles of acid, H⁺ = 0.007 × 0.258 moles = 0.001806 moles
Number of moles of KOH remaining, OH⁻= 0.05 × 0.129 - 0.001806 = 0.004644
Number of moles of OH⁻ = 0.004644 moles
[tex]Concentration, \ [OH^-] = \dfrac{0.004644 \, moles}{0.05 7 \, L} \approx \mathbf{ 0.0815 \, M}[/tex]
pH of solution = 14 - (-log(0.0815)) ≈ 12.91C) 12.5 mL HCl contains, 0.0125 × 0.258 moles = 0.003225 moles
OH⁻ remaining = 0.05 × 0.129 - 0.003225 = 0.003225 moles
[tex]Concentration \ of \ [OH^-]= \dfrac{0.003225\, moles}{(0.05 + 0.0125) \, L} = \mathbf{0.0516 \, M}[/tex]
pH of solution = 14 - (-log(0.0516)) ≈ 12.71D) 18.0 mL HCl contains, 0.018 × 0.258 moles = 0.004644 moles
OH⁻ remaining = 0.05 × 0.129 - 0.004644 = 0.001806 moles
[tex]Concentration \ of \ [OH^-] = \dfrac{0.001806\, moles}{(0.05 + 0.018) \, L} \approx \mathbf{0.0266\, M}[/tex]
pH of solution = 14 - (-log(0.0266)) ≈ 12.42E) 24.0 mL HCl contains, 0.024 × 0.258 moles = 0.006192 moles
OH⁻ ion remaining = 0.05 × 0.129 - 0.006192 = 0.000258 moles
[tex]Concentration \ of \ [OH^-] = \dfrac{0.000258\, moles}{(0.05 + 0.024) \, L} \approx \mathbf{0.0035\, M}[/tex]
pH of solution = 14 - (-log(0.0035)) ≈ 11.54F) 25.0 mL HCl contains, 0.025 × 0.258 moles = 0.00645 moles
[OH⁻] remaining = 0.05 × 0.129 - 0.00645 = 0 moles
[tex]Concentration \ of \ [OH^-] = \dfrac{0\, moles}{(0.05 + 0.024) \, L} \approx 0\, M[/tex]
Therefore;
Number of moles of KOH = 0, or the solution is neutralized
[OH⁻] = [H⁺]
Which gives;
pH = pOH = 7G) 26.0 mL HCl contains, 0.026 × 0.258 moles = 0.006708 moles
[OH⁻] remaining = 0.05 × 0.129 - 0.006708 = -0.000258 moles
Therefore
Number of moles of H⁺ = 0.000258
[tex]\mathbf{Concentration} \ of \ \mathbf{[H^+] }= \dfrac{0.000258\, moles}{(0.05 + 0.026) \, L} \approx 0.003395\, M[/tex]
pH of solution = (-log(0.003395)) ≈ 2.469H) 29.0 mL HCl contains, 0.029 × 0.258 moles = 0.007482 moles
H⁺ remaining = 0.007482 - 0.05 × 0.129 = 0.001032 moles
Therefore
Number of moles of H⁺ = 0.001032
[tex]Concentration \ of \ [H^+] = \mathbf{ \dfrac{0.001032\, moles}{(0.05 + 0.029) \, L}} \approx 0.01306\, M[/tex]
pH of solution = (-log(0.01306)) ≈ 1.884Learn more about the pH of a solution here:
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What is the solar radius of a main sequence star?
Answer:I'm going to give some fictitious values just so that we can get some perspective on the matter.
Let's say that the surface temperature of our sun is 10, the surface temp of the bigger star- the red giant formed from leaving the main sequence, has a temp of 0.2. of that- 2.
We can also say that the radius of our sun is 10, and the radius of the red giant is 1000. (100 times more)
Using the equation:
L
=
σ
A
T
4
σ
= The Stefan-Boltzmann constant =
5.67
×
10
−
8
But we can ignore the constant, as we are only interested in a ratio of these values.
L
S
u
n
=
4
π
(
10
)
2
×
10
4
=
1.26
×
10
7
L
S
t
a
r
=
4
π
(
1000
)
2
×
2
4
≈
2.01
×
10
8
2.01
×
10
8
1.26
×
10
8
≈
16
So the newly formed, red giant star is almost 16 times more luminous than the sun. This is owing to the increased surface area of the star due to the massively increased radius.
A small sidenote:
There is an equation that might be useful for comparing the radii, temperature and luminosity of main sequence stars. As red giants are not on the main sequence it could not be used here, but if you stumble across a question where they ask you to find the radius, luminosity or temperature given the other two, you can relate it to the sun's characteristics:
r
s
t
a
r
r
s
u
n
=
√
L
s
t
a
r
L
s
u
n
×
(
T
s
u
n
T
s
t
a
r
)
2
(I know, it's not a beauty to look at- but it works)
Where
X
s
u
n
is the radius, temperature, and luminosity of the sun. These are not often given in numerical values, but this equation serves well when asked to find e.g the radius of a star, in solar radii given that a star is twice as luminous and has 5 times the temperature of that of the sun.
Hence:
T
s
t
a
r
=
5
T
s
u
n
L
s
t
a
r
=
2
L
s
u
n
r
s
t
a
r
r
s
u
n
=
√
2
L
s
u
n
L
s
u
n
×
(
T
s
u
n
5
T
s
u
n
)
2
(cancel the common terms)
r
s
t
a
r
r
s
u
n
=
√
2
×
(
1
5
)
2
r
s
t
a
r
≈
0.057
r
s
u
n
(divide both sides by 0.0057)
17.5
r
s
t
a
r
≈
r
s
u
n
So the star's radius is almost 17.5 times that of the sun.
Hopefully, you find this info useful!
Explanation:
structure of 2,6-diiodo-4-methyl-5-propylheptane
Answer:
diiodo????
Explanation:
recheck the question and resend
Mixing hydrochloric acid and sodium hydroxide is an example of an exothermic
reaction. This means...
Select one
energy is taken in during the chemical reaction
hydrochloric acid and sodium hydroxide are the products of the reaction
Energy released during the chemical reaction
There is no change in energy during the chemical reaction
Answer:
exothermic means that energy was released during the chemical reaction
Explanation:
Two identical spoons are electroplated with Ag or Cd through the use of the electrolytic cells. A current of 5.00A was supplied to each cell for 600. seconds, and the masses of the spoons before and after the electroplating were recorded. Write down the mathematical equations can best be used to account for the much larger increase in mass of the spoon electroplated with Ag compared with the spoon electroplated with Cd.
Answer:
Explanation:
One farad of charge is capable of depositing one gram equivalent of a metal
One gram equivalent of Ag = 108 grams
One gram equivalent of Cd = 112 / 2 grams
= 56 grams . [ for cadmium equivalent mass = atomic mass / s ]
electric charge flowing = current x time = 5 x 600 = 3000 coulomb
one farad = 96500 coulomb
96500 coulomb deposits 108 gram of Ag
3000 coulomb deposits 108 x 3000 / 96500 gram
= 3.35 grams of Ag
Similarly ,
96500 coulomb deposits 56 gram of Cd
3000 coulomb deposits 56 x 3000 / 96500 gram
= 1.74 grams of Cd
So there will be much larger increase in the spoon of Ag due to larger deposit of Ag by charge .
When do Florida plants prepare themselves for the cold winter temperatures? (1 point)
a
Beginning of the spring
b
During the fall
c
End of the spring
d
End of the summer
PLEASE HELP ASAP!!! >.
Answer:
A. Beginning of the spring
Explanation:
Pa like, Pa follow, Pa rate
What is a mixture of two insoluble mixtures called
Answer:
Emulsion
Explanation:
Emulsion is a special type of mixture formed by combining two liquids that do not normally mix. An example of emulsion is;
Oil and Water
Fill in the blank with the correct answer to complete the sentence.
Word bank
size
velocity
distance
time
Momentum increases with an increase in mass and
Explanation:
momentum increases with an increase in mass and velocity
1. A solution is always a mixture (true or false)
im not sure what the answer is so if anyone could help me that would be great
(ps im in 5th grade)
Answer:
yes solution is always a mixture but not all mixtures are solution
Explanation:
A solution.is a homogeneous mixture of substance that have uniform composition throughout
And a mixture hVe twoo or more substances that are not chemically.combine
A combustion reaction involves the reaction of a substance with oxygen gas. The complete combustion of any hydrocarbon (binary compound of carbon and hydrogen) produces carbon dioxide and water as the only products. Heptane is a hydrocarbon that is found in gasoline. Complete combustion of heptane produces 7 liters of carbon dioxide for every 8 liters of water vapor (both measured at the same temperature and pressure). What is the ratio of carbon atoms to hydrogen atoms in a molecule of heptane
Answer:
7/16
Explanation:
The general formula for the combustion of alkanes is;
CnH2n+2 + 3n+1/2 O2 -------> nCO2 + (n+1)H2O
So, we have;
CnHn + nO2 ------> 7CO2 + 8H2O
So there are 7 carbon atoms and 16 hydrogen atoms in heptane according to the law of conservation of mass.
Therefore, heptane is; C7H16
The ratio of carbon to hydrogen is now; 7/16
Write True if the statement is correct and False if it is incorrect.
1. Mosquitos are flies.
2. All large invertebrates live in the
sea or at least in water.
3. An arthropod is a form of arachnid.
4. The giant squid is the world's largest
invertebrate.
5. Earthworms have skeleton
6. The octopus is the most advance of
the mollusks.
7. Insects are vertebrates animals.
8. Starfish have shells.
9. Snails have spiral protective shell.
10. Ants and termites both live in colonies
with a complex social structure.
A per the statement the true and false have been stated.
The mosquitos are flies is True. All large invertebrates live in the sea or at least in water is False. An arthropod is a form of arachnid. False. The giant squid is the world's largest invertebrate is true. Earthworms have skeleton is false. An octopus is the most advance of the mollusks is True. Insects are vertebrates animals is false . Most starfish have shells is true. All Snails have a spiral protective shell is true. The Ants and the termites both live in their colonies with a complex social structure true.Learn more about the statement is correct and False if it is incorrect.
brainly.com/question/25942470.
Salt of a weak acid with strong base When
dissolved in water gives?
Answer:
it gives base, it is process of neutralization,when acid reacts with base it gives salt and water
Which of the following is the best example of water changing from a liquid to a gas?
A. clouds on a summer day
B. morning dew on orange trees
C. fog rising from a pond on a cold day
D. ice melting back to water when it is left out at room temperature
Answer:
c
Explanation:
hope this helps! ^-^
Answer:
C
Explanation:
It's the answer
What is the density of an object with mass 80 kg and volume 05 cubic meters
Answer:
mesure it
Explanation:
I HAVE 25 MINUTES TO FINISH True or false the deeper you go into Earth the temperature goes up ?
Answer:
true
Explanation:
you are getting closer to the core hope this helps!
How does ice float on water?
Why does solid ice float on liquid water?
Answer:
Explanation:
Solid ice floats over water because ice is less dense than liquid water, or weighs less, by about 10%, than liquid water
Which gas is described incorrectly in the passage?
(The answer choices are the capitalized words)
Gases such as carbon dioxide, nitrogen, and oxygen are constantly recycled in the atmosphere through different processes. For example, plants absorb CARBON DIOXIDE and releases OXYGEN during photosynthesis. On the other hand, plants and animals both take in oxygen and release CARBON DIOXIDE is removed from the atmosphere by the process of rock weathering.
Answer:
Nice
Explanation:
The law that states when different compounds are formed by a combination of the same elements, different masses of one element combine with the same fixed to other elment
Answer:
The law of multiple proportions states that whenever the same two elements form more than one compound, the different masses of one element that combine with the same mass of the other element are in the ratio of small whole numbers.
why metals are good conductor of electricity
Explanation:
silver is the best conductor
Answer:
Metals are an excellent conductor of electricity and heat because the atoms in the metals form a matrix through which outer electrons can move freely. Instead of orbiting their respective atoms, they form a sea of electrons that surround the positive nuclei of the interacting metal ions
Examining the equations or equilibrium constants related to a base, salt, or an acid is an indirect way to determine strength of an electrolyte. The strength of an electrolyte can be examined directly by placing a solution into a circuit so that the voltage or amount of current can be measured. Although conductivity refers to the flow of charged species, we usually examine conductivity with respect to resistance. As the name implies, a solution that does not conduct electricity very well also has a very high resistance. If solutions containing various acids, bases, and salts were prepared and connected to a circuit that powers a light bulb, the strength of the electrolyte could be estimated by examining the intensity of the light bulb. Complete the following sentences regarding the experimental determination of the electrolyte strength for various molecules dissolved in solution.
a. strong electrolyte
b. weak electrolyte
c. non-electrolyte
1. A 20 mL solution containing 2 mmol of Ca3(PO4)2(s) was integrated into to a circuit that powers a light but, When the power supply was turned on, the light bulb produced a glow. Ca3(PO4)2(s) is__.
2. A 20 mL, solution containing 2 mmol of C12H22O11(aq) was integrated into a circuit that powers a light bulb. When the power supply was turned on the light bulb remained off. C12H22O11(aq) is___.
3. A 20 mL, solution containing 2 mmol of HF(g) was integrated into to a circuit that power a light bulb. When the power supply was turned on the light bulb faintly flickered. HF(g) is an____.
4. A 20 mL solution containing 2 mmol of LiOH(g) was integrated into to a circuit that power a light bulb. When the power supply was turned on the light bulb produced a bright glow LiOH(s) is a____.
Answer:
1 - Weak electrolyte
2- Non electrolyte
3- Weak electrolyte
4- Strong electrolyte
Explanation:
A strong electrolyte refers to an electrolyte that decomposes completely in solution. This means that there are more charge carriers in solution when a strong electrolyte is dissolved in water. A strong electrolyte produces a strong glow. LiOH is a strong electrolyte.
A weak electrolyte is not completely dissociated in water. Only a small amount dissociates in water. HF is a weak electrolyte. A weak electrolyte does not produce a bright light.
A non-electrolyte does not dissociate in solution at all hence it does not power a bulb E.g C12H22O11.
Please help quickly as possible thank you :)
Ce clasă ești sa văd daca te pot ajuta
List four kinds of energy. Give a brief definition of each.
Answer:
Mechanical Energy- Energy that result from movement or the location of the object. Is the sum of kinetic and potential energy.
Thermal Energy- Thermal energy or heat energy reflects the temperature difference between two systems.
Nuclear Energy- is energy resulting from changes in the atomic nuclei or from nuclear reactions.
Chemical Energy- results from chemical reactions between atoms or molecules.
More:
Kinetic energy- is the energy of motion of a body. It ranges from 0 to a positive value.
Electromagnetic energy- (or radiant energy) is energy from light or electromagnetic waves.
Sonic energy- is the energy of sound waves. Sound waves travel through the air or another medium.
Gravitational energy- energy associated with gravity involves the attraction between two objects based on their mass.
Ionization energy- is the form of energy that binds electrons to the nucleus of its atom, ion, or molecule.
Potential energy- is the energy of an object's position.
Explanation:
Hope this helps
How many pounds of ice are required to absorb 4900 kJ of heat as the ice melts? The heat of fusion of water is 0.334 kJ/g.
help pls
Answer:
Q = ΔH fusion * mass (g)
when we have:
ΔH fusion (the heat (or enthalpy) of fusion = 0.334 kJ/g
and mass of ice = 22.4 g
so by substitution, we can get the energy (Q) required to melt this mass of ice:
∴ Q = 0.334KJ/g * 22.4 g
= 7.48 KJ
∴ the energy required to melt 22.4 g of ice is = 7.48 KJ
Explanation:
what the the noble gas configuration for krypton
Answer:
[Ar] 3d¹⁰ 4s² 4p⁶
Explanation:
Krypton is a chemical element with the symbol Kr and atomic number 36. It is a colorless, odorless, tasteless noble gas that occurs in trace amounts in the atmosphere and is often used with other rare gases in fluorescent lamps. With rare exceptions, krypton is chemically iner,
Animals get energy from the food that they eat. However, when the molecules from the food enter your cells, how do the molecules turn in to energy?
Question 3 options:
The glucose molecules from the food are broken down by the mitochondria in the cell to produce ATP which the cells use as energy.
The ATP is broken down into glucose which the cells use for energy.
Upon hitting the stomach, the food molecules are changed to energy molecules which fuel the body.
The cells absorb ATP from food and use it for energy.
Answer:
The ATP is broken down into glucose which the cells use for energy.
Fill in the [?]: 5,481 g = [?] lb.
Answer:
12.084 lb
Explanation:
1 gram = 0.00220462 lb
multiply number of grams by 0.00220462
Ex. 2000 g x 0.00220462 = 4.409 pounds
A Period 2 element has the following successive ionization energies. Identify the element...
1st: 1087 kJ/mol
2nd: 2353 kJ/mol
3rd: 4621 kJ/mol
4th: 6223 kJ/mol
5th: 37832 kJ/mol
6th: 47279 kJ/mol
7th: 55261 kJ/mol
8th: 69875 kJ/mol
Answer:
9th:08473 kJ/mol
Explanation:
HAHAHAHAHAHAHAHAHAHA
1) De los siguientes cambios indicar cuál es químico y cual es físico:
• Aplastar una lata:
• Congelar agua:
• Quemar pasto:
• Hervir agua:
• Se descompone fruta:
• Se oxida hierro:
• Derretir chocolate:
• Mezclar agua y sal:
• Pulverizar un ladrillo:
• Quemar pólvora