Answer:
jhdgafhgafhagfhafg
Explanation:
Check all that apply...helppppp
Answer:
dfgh
Explanation:
How is water used in society
Answer:
Water can be used for direct and indirect purposes. Direct purposes include bathing, drinking, and cooking, while examples of indirect purposes are the use of water in processing wood to make paper and in producing steel for automobiles. The bulk of the world's water use is for agriculture, industry, and electricity.
Explanation:
Answer:
water is used for drinking, bathing, cooking, agriculture etc
Which of the following astronomical bodies would most likely be the largest?
1. A dwarf star from a nearby solar system
2. A comet
3. One of the gas giants in our solar system
4. Ganymede, the largest moon of Jupiter
Answer:
1
because a dwarf star will seemlarge because of the in ability of any human being to see d sun
What is the energy of an electron in a Li+ ion when an electron moves from n = 2 to n =3?
Answer:
The question wants you to determine the energy that the incoming photon must have in order to allow the electron that absorbs it to jump from
n
i
=
2
to
n
f
=
6
.
A good starting point here will be to calculate the energy of the photon emitted when the electron falls from
n
i
=
6
to
n
f
=
2
by using the Rydberg equation.
1
λ
=
R
⋅
(
1
n
2
f
−
1
n
2
i
)
Here
λ
si the wavelength of the emittted photon
R
is the Rydberg constant, equal to
1.097
⋅
10
7
m
−
1
Plug in your values to find
1
λ
=
1.097
⋅
10
7
.
m
−
1
⋅
(
1
2
2
−
1
6
2
)
1
λ
=
2.4378
⋅
10
6
.
m
−
1
This means that you have
λ
=
4.10
⋅
10
−
7
.
m
So, you know that when an electron falls from
n
i
=
6
to
n
f
=
2
, a photon of wavelength
410 nm
is emitted. This implies that in order for the electron to jump from
n
i
=
2
to
n
f
=
6
, it must absorb a photon of the same wavelength.
Fires are classified into various classes and as such different types of portable fire extinguishers must be used. The theory behind portable fire extinguishers is that the fire can be extinguished by removing any or more of the following four elements:
Fuel, Heat, Oxygen, Chain Reaction.
Identify the extinguishing mechanism and the classe(s) of fires they are used to extinguish for the following types of fire extinguishers:
ABC Powder, Carbon dioxide, Foam, Water.
Answer:
Explanation:
ABC Powder: sprays a very fine chemical powder. This acts to blanket the fire and suffocate it. Class A, B, C fires
Carbon dioxide: extinguishes CO2. By doing so, it removes oxygen from the fire, effectively suffocating it of oxygen. Class B fires
Foam: spray a type of foam that expands when it hits the air and blankets the fire. This prevents the vapors from rising off the liquid to feed the fire, thus starving it of fuel. Class A and B
Water: releases microscopic water molecules that fight the fire on a variety of levels. the level of oxygen in the air is decreased, which helps to suffocate the fire. Class: most all
also, your fire classes:
Class A: freely burning, combustible solid materials such as wood or paper
Class B: flammable liquid or gas
Class C: energized electrical fire (energized electrical source serves as the ignitor of a class A or B fire – if electrical source is removed, it is no longer a class C fire)
Class D: metallic fire (titanium, zirconium, magnesium, sodium)
Class K: cooking fires – animal or vegetable oils or fats
In the process of photosynthesis, sunlight is converted into
Answer:
Chemical energy
Explanation:
By the use of electrons and protons from water
Answer:
chemical energy
Explanation:
Photosynthesis is the process by which organisms that contain the pigment chlorophyll convert light energy into chemical energy which can be stored in the molecular bonds of organic molecules (e.g., sugars). Photosynthesis powers almost all trophic chains and food webs on the Earth.
What is the reducing agent in the following reaction?
2 Br−(aq) + H2O2(aq) + 2 H+(aq) → Br2(aq) + 2 H2O(l)
Answer:
the reducing agent is Bromine
The oxidation state of an element is calculated by subtracting and the total sum of oxidation states of all the individual atom (excluding the one that has to be calculated) from total charge on the molecule. Bromine is the reducing agent in the following reaction.
What is oxidation state?Oxidation state of an element is a number that is assigned to an element in a molecule that represents the number of electron gained or lost during the formation of that molecule or compound.
The ionic equation is given as
2 Br⁻(aq) + H[tex]_2[/tex]O[tex]_2[/tex](aq) + 2 H⁺(aq) → Br[tex]_2[/tex](aq) + 2 H[tex]_2[/tex]O(l)
The oxidation state of bromine on reactant side is -1 while on product side it is 0 so, oxidation state of bromine has increased by 1 so, bromine is oxidized. If it is oxidized that means it must have reduced someone. So, bromine is acting as a reducing agent.
Therefore, bromine is the reducing agent in the given reaction.
To learn more about Oxidation state, here:
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Name 3 ways you can keep our community healthy?
Answer:
1. Practice healthy habits with kids in your life. ...
2. Engage in your school's efforts to encourage healthy practices. ...
3. Learn more about the decisions local officials are making that impact your environment. ...
4. Give back healthy options to your community.
Explanation:
Which do you use to qualify matter?
A. Thermometer
B. Five senses
C. Balance
D. Tape measure
Answer:
c balance
Explanation:
if you weigh something, you prove it's there.
Explain in detail how low density polyethylene is made
Answer:
Low-density polyethylene is manufactured by the process of the polymerization of ethylene at very high temperatures in a tubular reactor. In this tubular reactor, high-pressure polymerization allows further copolymerization of ethylene with polar co-monomers. The tubular process has an advantage over autoclave process.
Explanation:
please mark brainliest
Do not abuse or misuse any piece of drawing instrument. ASAPPPP
7. Which of the following is a proof that light travels in a straight line?
A. Formation of clouds
C. Formation of rainbows
B. Formation of colors
D. Formation of shadow
Answer:
formation of shadow is right
Answer:
correct answer is D
Explanation:
When you see a shadow, it is directly behind the object.
Five identical test tubes are each filled from the following five copper (11) sulfate stock solutions. Which of the following test tubes would appear the lightest blue?
a) Stock solution made form 0.200 moles of CuSO4 dissolved to a total volume of 400 ml
b) Stock solution made form 0.150 moles of CuSO4 dissolved to a total volume of 300 mL
C)Stock solution made form 0.250 moles of CuSO4 dissolved to a total volume of 500 ml
d) Stock solution made form 0.175 moles of CuSO4 dissolved to a total volume of 400 ml
e) Stock solution made form 0.125 moles of CuSO4 dissolved to a total volume of 300 ml
Answer:
deez cutz
Explanation:
did i get it right
Make a
prediction about how a lack
of resources in an ecosystem
might impact the levels of
organization.
Answer:
Limiting factors of an ecosystem include disease, severe climate and weather changes, predator-prey relationships, commercial development, environmental pollution and more. An excess or depletion of any one of these limiting factors can degrade and even destroy a habitat.
Explanation:
The limiting factor of an ecosystem involve disease, weather change, climate change, environment pollution and more. An excess or depletion of any of these factor can destroy over habitat.
What is Ecosystem?An ecosystem is define as a community or a group of living organisms that live together and are dependent on each other.
There are two main types of ecosystem.
Terrestrial ecosystem-Terrestrial ecosystem are land based ecosystem and interaction of biotic and abiotic component in the specific area.
Example- forest, grassland desert etc.
Aquatic ecosystem-Aquatic ecosystem are ecosystem formed by surrounding water bodies. They are dependent on each other and their environment .
Example- lake, pond, river etc.
Thus ecosystem and their limiting factor have great impact on the level of organization.
To learn more about ecosystem, refer to the link below:
https://brainly.com/question/13979184
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How many mL of 0.100M Ca(OH) are needed to titrate 20.0mL of 0.300M H2SO4
Answer:
60.0 mL
Explanation:
Using CAVA = CBVB
CA = 0.300M
VA = 20.0 mL
CB = 0.100M
VB = ?
VB = CAVA
CB
VB = 0.300 * 20/ 0.100
VB = 60.0 mL
Please Need help asap
For Al, its atomic number is 13 and its mass number is 27. How many neutrons does it have?
А. 13
B. 14
C. 26
D. 27
E. 40
Answer:
A
Explanation:
The number of protons and neutrons of an element is the same. the electrons are the only thing that can differ. The atomic number equal the protons and neutrons.
100.00 mL of 0.15 M nitrous acid (HNO2) are titrated with a 0.15 M NaOH solution. (a) Calculate the pH for the initial solution. (b) Calculate the pH for the point at which 80.0 mL of the base has been added. (c) Calculate the pH for the equivalence point. (d) Calculate the pH for the point at which 105 mL of the base has been added.
Answer:
a. pH = 2.04
b. pH = 3.85
c. pH = 8.06
d. pH = 11.56
Explanation:
The nitrous acid is a weak acid (Ka = 5.6x10⁻⁴) that reacts with NaOH as follows:
HNO₂ + NaOH → NaNO₂(aq) + H₂O(l)
a. At the beginning there is just a solution of 0.12M HNO₂. As Ka is:
Ka = [H⁺] [NO₂⁻] / [HNO₂]
Where [H⁺] and [NO₂⁻] ions comes from the same equilibrium ([H⁺] = [NO₂⁻] = X):
5.6x10⁻⁴ = X² / 0.15M
8.4x10⁻⁵ = X²
X = [H⁺] = 9.165x10⁻³M
As pH = -log [H⁺]
pH = 2.04b. At this point we have HNO₂ and NaNO₂ (The weak acid and the conjugate base), a buffer. The pH of a buffer is obtained using H-H equation:
pH = pKa + log [NaNO₂] / [HNO₂]
Where pH is the pH of the buffer,
pKa is -log Ka = 3.25
And [NaNO₂] [HNO₂] could be taken as the moles of each compound.
The initial moles of HNO₂ are:
0.100L * (0.15mol / L) = 0.015moles
The moles of base added are:
0.0800L * (0.15mol / L) = 0.012moles
The moles of base added = Moles of NaNO₂ produced = 0.012moles.
And the moles of HNO₂ that remains are:
0.015moles - 0.012moles = 0.003moles
Replacing in H-H equation:
pH = 3.25 + log [0.012moles] / [0.003moles]
pH = 3.85c. At equivalence point all HNO2 reacts producing NaNO₂. The volume added of NaOH must be 100mL. That means the concentration of the NaNO₂ is:
0.15M / 2 = 0.075M
The NaNO₂ is in equilibrium with water as follows:
NaNO₂(aq) + H₂O(l) ⇄ HNO₂(aq) + OH⁻(aq) + Na⁺
The equilibrium constant, kb, is:
Kb = Kw/Ka = 1x10⁻¹⁴ / 5.6x10⁻⁴ = 1.79x10⁻¹¹ = [OH⁻] [HNO₂] / [NaNO₂]
Where [OH⁻] = [HNO₂] = x
[NaNO₂] = 0.075M
1.79x10⁻¹¹ = [X] [X] / [0.075M]
1.34x10⁻¹² = X²
X = 1.16x10⁻⁶M = [OH⁻]
pOH = -log [OH-] = 5.94
pH = 14-pOH
pH = 8.06d. At this point, 5mL of NaOH are added in excess, the moles are:
5mL = 5x10⁻³L * (0.15mol / L) =7.5x10⁻⁴moles NaOH
In 100mL + 105mL = 205mL = 0.205L. [NaOH] = 7.5x10⁻⁴moles NaOH / 0.205L =
3.66x10⁻³M = [OH⁻]
pOH = 2.44
pH = 14 - pOH
pH = 11.56What is the molar mass of AlCl3
Answer:
133.34 g/moles
Explanation:
but to make life easy it could be 133.4 g/ moles as well
Why is the method of using a density bottle more accurate than the measuring cylinder
Answer:
While measuring relative density of liquids, two common method of measuring the volume are a measuring cylinder and a density bottle. Among these two method the density bottle gives more accurate measurement of the volume, resulting in more accurate determination of density or relative density
Answer:
While measuring relative density of liquids, two common method of measuring the volume are a measuring cylinder and a density bottle. Among these two method the density bottle gives more accurate measurement of the volume, resulting in more accurate determination of density or relative density.
Explanation:
45. What is the H ion concentration of an aqueous solution
in which the OH-ion concentration is 1 x 10-2 mole
per liter?
A) 1 X 10-14 M
C) 1 x 10-9M
B) 1 x 10-12 M
D) | 10-2M
Answer:
= 1 X 10⁻⁻¹²M
Explanation:
At 25°C & 1atm [H⁺][OH⁻] = 1 x 10⁻¹⁴ => [H⁺] = 1 X 10⁻¹⁴/[OH⁻] = 1 X 10⁻¹⁴/1 X 10⁻²
= 1 X 10⁻⁻¹²M
Which overall chemical equation is obtained by combining these intermediate equations?
What is the pressure inside a container of 3 moles of gas with a volume of 60 Liters at a temperature of 400 K?
I just need the answer not a link please :)
A compound with an approximate molar mass of
65.0g/mol is made up of C, H and Cl. This same
Compound contains 55% of Cl by mass .lf 9g
of the compound contains 4.19 x 10²³ atoms,
determine the compound's:
a empirical formular and molecular formular
What is the name of the structure formed when fertilization occurs?
Answer:
zygote
Explanation:
I got this online
Answer:
ᘔYᘜOTᗴ:=> In human fertilization, a released ovum (a haploid secondary oocyte with replicate chromosome copies) and a haploid sperm cell (male gamete)—combine to form a single 2n diploid cell called the zygote.
ʰᵒᵖᵉ ⁱᵗ ʰᵉˡᵖˢ
[tex] \infty \infty [/tex]
how many moles are there in 2.20 x 10^23 molecules of Na2SO4
Answer:
Explanation:
450 grams of Na2SO4? 450 Na soullnol Na2SO4 16.02x1023 molec, Na₂SO4 = 119x1024. | 142.05g Na25041 Imol Naz
A 50.0 mL sample of an aqueous H2SO4 solution is titrated with a 0.375 M NaOH solution. The equivalence point is reached with 62.5 mL of the base. The concentration of H2SO4 is ________ M. A 50.0 mL sample of an aqueous H2SO4 solution is titrated with a 0.375 M NaOH solution. The equivalence point is reached with 62.5 mL of the base. The concentration of H2SO4 is ________ M. 0.150 0.234 0.300 0.469 0.938
Answer: The concentration of [tex]H_2SO_4[/tex] is 0.234 M
Explanation:
According to the neutralization law,
[tex]n_1M_1V_1=n_2M_2V_2[/tex]
where,
[tex]n_1[/tex] = basicity [tex]H_2SO_4[/tex] = 2
[tex]M_1[/tex] = molarity of [tex]H_2SO_4[/tex] solution = ?
[tex]V_1[/tex] = volume of [tex]H_2SO_4[/tex] solution = 50.0 ml
[tex]n_2[/tex] = acidity of [tex]NaOH[/tex] = 1
[tex]M_1[/tex] = molarity of [tex]NaOH[/tex] solution = 0.375 M
[tex]V_1[/tex] = volume of [tex]NaOH[/tex] solution = 62.5 ml
Putting in the values we get:
[tex]2\times M_1\times 50.0=1\times 0.375\times 62.5[/tex]
[tex]M_1=0.234M[/tex]
Therefore concentration of [tex]H_2SO_4[/tex] is 0.234 M
Plz answer the first two questions and maybe the third. I will give brainliest.
Answer:
1. 24.45 moles
2. 437.90 grams
Bonus :
0.75 grams
Explanation:
Hope it was helpful ;)
A mixture of NO2 and N2O4 gas is at equilibrium in a closed container. These gases react with the equation 2NO2 ⇌ N2O4. What will happen if the size of the container is increased?
Answer:
Equilibrium will shift leftwards towards NO2.
Explanation:
Hello there!
In this case, according to the Le Cha telier's principle, it is possible to realize that the increase of the volume turns out in the shift towards the most of the gaseous moles are in; in such a way, for the given chemical reaction, we can notice how NO2 (reactant side) has the most of the moles (2 moles in comparison to 1 mole of N2O4); and therefore, by increasing the volume, the equilibrium will shift to it, it means leftwards.
Best regards!
Is anyone good at chemistry if so can someone help me please ?
(NO LINKS)
Question 15
We're given the [OH⁻] as 8.34 × 10⁻¹² M. Using the formula pOH = -log[OH⁻], the pOH of this solution would be -log(8.34 × 10⁻¹²) ≈ 11.08.
The pOH is, for lack of a better term, the "opposite" of pH: A pOH of 7 is neutral; a pOH less than 7 is basic; and a pOH greater than 7 is acidic.
This follows from the relation, pH + pOH = 14. In this case, with a pOH of 11.08, our pH would be 14 - 11.08 = 2.92, which is acidic (pH < 7).
Thus, the correct answer choice is B.
Worth 100 points plus ill mark brainliest
How many grams of sodium phosphate ( Na₃PO₄ )are required to make 125 milliliters of a 0.240 Molar solution?
4.92
6.48
8.44
12.5
Answer:
4.92 grams of sodium phosphate (Na₃PO₄) are required to make 125 milliliters of a 0.240 M.
Explanation:
Molarity is a measure of concentration that indicates the number of moles of solute that are dissolved in a given volume.
The molarity of a solution is calculated by dividing the moles of the solute by the volume of the solution:
[tex]Molarity=\frac{number of moles}{volume}[/tex]
Molarity is expressed in units [tex]\frac{moles}{liter}[/tex].
In this case:
Molarity= 0.240 Mnumber of moles= ?volume= 125 mL= 0.125 LReplacing in the definition of molarity:
[tex]0.240 M=\frac{number of moles}{0.125 L}[/tex]
Solving:
number of moles= 0.240 M*0.125 L
number of moles= 0.03 moles
Being the molar mass of sodium phosphate 164 g/mole, that is, the mass of one mole of the compound, you can calculate the mass of 0.03 moles using the following rule of three: if 1 mole of the compound has 164 grams, 0.03 moles contains how much mass?
[tex]mass=\frac{0.03 moles*164 grams}{1 mole}[/tex]
mass= 4.92 grams
4.92 grams of sodium phosphate (Na₃PO₄) are required to make 125 milliliters of a 0.240 M.
