Answer:
3
helium
Explanation:
Among all the given options, the correct option is option 3. An element that is considered to be unreactive because it has a filled outer energy level is helium.
What is element?Any compound that cannot be broken down into simpler chemicals by regular chemical processes is referred to as a chemical element or element. The building blocks of which every matter is made are called elements.
There are 118 chemical elements that are currently recognized. About 20% of them have only been created synthetically in the lab and are only known because they do never exist in nature or are only present in trace levels. An element that is considered to be unreactive because it has a filled outer energy level is helium.
Therefore, among all the given options, the correct option is option 3.
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explain the formation and breakdown of polymers?
Answer: Polymers are broken down into monomers via hydrolysis reactions, in which a bond is broken, or lysed, by addition of a water molecule. ... This is the reverse of a dehydration synthesis reaction, and it releases a monomer that can be used in building a new polymer.
Which of the following is an example of hydrogen bonding?
Answer:
water H2O
Explanation:
HURRY
Show step-by-step
2A + 5B --> 3C + D
2.0 mol A and 4.0 mol B react to form 1.8 mol C. What is the PERCENT YIELD of this reaction?
Answer:
Percent yield of reaction is 75%.
Explanation:
Given data:
Moles of A = 2.0 mol
Moles of B = 4.0 mol
Moles of C formed = 1.8 mol
Percent yield of reaction = ?
Solution:
Chemical equation:
2A + 5B → 3C + D
We will compare the moles of A and B with C from balance chemical equation.
A : C
2 : 3
B : C
5 : 3
4 : 3/5×4 = 2.4 mol
Number of moles of C formed by 4 moles B are less thus B is limiting reactant and will limit the yield of C.
Percent yield:
Percent yield = actual yield /theoretical yield × 100
Percent yield = 1.8 mol / 2.4 × 100
Percent yield =75%
Data for CH3COOH(l) + C2H5OH(l) CH3COOC2H5(l) + H2O(l) balance were obtained at 100. The initial concentrations of the reagents are indicated in columns 1 and 2 of the table below and the CH3COOC2H5 concentrations in equilibrium are given in column 3. Calculate H2O and determine the value of KC
Answer:
Kc = 3.94
Explanation:
CH₃COOH(g) + C₂H₅OH(g) → CH₃COOC₂H₅(g) + H₂O(g)
Liquids aren't included in the equilibrium constant, but at 100°C, all four compounds are a gas. So the equilibrium equation is:
Kc = [CH₃COOC₂H₅] [H₂O] / ([CH₃COOH] [C₂H₅OH])
Set up an ICE table for each row and calculate the value of Kc. Then average the results. (See picture.)
Kc ≈ (3.919 + 4.012 + 3.902) / 3
Kc ≈ 3.94
Determine the length of the object shown.
5.6 cm
5.60 cm
5.600 cm
6 cm
Answer: The length of the object is 5.6 cm.
Explanation:
Describe the flow of energy through an ecosystem from the Sun to the plant and ultimately through an animal.
Answer:
Hope this Helps! :)
Explanation:
The word ecosystem refers to the all of the living species as well as non-living elements in a particular environmental area. For instance, a lake, swamp, coral reef, forest, or a prairie would each be considered an ecosystem. Ecosystems can vary greatly in size and individual characteristics -- for instance, the ecosystem of a puddle differs greatly from that of a swath of tundra.
Despite these disparities, all ecosystems function similarly in the way in which energy flows into, through, and out of them through the energy cycle
Energy is transferred into and out of ecosystems via a web of complex interactions. Energy enters an ecosystem from external sources and moves throughout its components. For instance, energy from the sun flows through plants, microorganisms, and animals. Energy cycles in an ecosystem end with decomposition, and then the process begins anew
Essentially, the flow of energy through ecosystems can be explained by who eats what. Keep in mind, however, that energy transfer isn’t perfectly efficient; much of it dissipates as heat at various phases in the cycle.
The energy flows from the sun to the plants by photosynthesis and animal eats plants and energy is transferred from plants to animals.
What is the transfer of energy?The energy transfer isn't entirely efficient because a significant amount of it evaporates as heat at different points throughout the cycle.
Despite these differences of energy, all ecosystems function similarly in terms of the energy cycle, which governs how energy enters, passes through, and exits them.
Ecosystems receive and expend energy through a network of intricate interconnections. An ecosystem receives energy from outside sources, which circulates among its parts.
Thus, as a result of photosynthesis, energy is transmitted from the sun to plants, which are then consumed by animals.
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Explain how some salt solutions can be heavy and some light if they are made
with the same materials.
Answer:??????
Explanation:
What two factors affect the rate of acceleration of an object?
O force and distance
mass and weight
O force and mass
Answer:
force and mass
Explanation:
This table shows the mass and volume of four different objects.
A two-column table with 4 rows. The first column titled objects has entries W, X, Y, Z. The second column titled Measurements has entries Mass: 16 grams Volume: 84 centimeters cubed in the first cell, Mass: 12 grams Volume: 5 centimeters cubed in the second cell, Mass: 4 grams Volume: 6 centimeters cubed in the third cell, Mass: 408 grams Volume: 216 centimeters cubed in the fourth cell.
Which ranks the objects from most to least dense?
X, Y, W, Z
X, Z, Y, W
W, Y, Z, X
Z, Y, X, W
Answer:
x, y, w, z
Explanation:
hope it’s right, but i think it is :)
Answer:
x y w z
Explanation:
Show the formation of Calcium chloride by the transfer of electrons
Answer:
CaCl,2
the 2 goes to the bottom right side
Complete orbital diagrams (boxes with arrows in them) to represent the electron configuration of valence electrons of carbon before and after sp hybridization.
Answer:
Explanation:
Before Hybridization => C: 1s² ⇵ 2s²⇵ 2p₋₁↑ 2p₀↑ 2p₊₁∅
After Hybridization => C: 1s² 2sp¹ 2sp¹ 2p₀¹2p₊₁¹ => 2 hybrid orbitals and 2 unhybridized p-orbitals at the n=2 energy level.
how many grams of Br2 are needed to completely convert 15.0g Al to Albr3?
Answer:
For, this question,
The balanced equation is; 2Al + 3 ----> 2Al
We can now, calculate how many grams of will be needed to completely convert 15 g of Al into Al.
Here, the reaction produces, 2 moles of Al
So, For 15.0 g of Al; we can calculate;
(15.0 g Al) X (1 mole Al / 26.98 g Al) X (3 moles / 2 moles Al) X (159.81 g / 1 mole )
= 133 g of will be needed.
Therefore, 133g of will be needed to completely convert 15 g of Al into Al.
Explanation:
By what means (or force) can the atoms in compounds be separated?
Answer:
chemical means
Explanation:
Compounds can be separated by chemical means physical means boiling pressure
Is fireworks exploding a chemical change?
Answer:
Yes
Explanation:
The fireworks explode
Answer:
The explosion of fireworks is an example of chemical change. During a chemical change, substances are changed into different substances. In other words, the composition of the substance changes.
A reaction of chlorine gas with sodium solid creates 45.6 grams of sodium chloride. The mass of sodium and chlorine gas price for the reaction was ___ grams
Answer:
17.94 annd 27.69 respectively.
Explanation:
Na(s) + Cl(g) n` NaCl(s)
mass of NaCl = 45.6 g
Mr of NaCl = 23 + 35.5
= 58.5g/mol
mole of NaCl = mass/Mr
= 45.6/58.5
= 0.78 moles
From the equation;
1 mole of NaCl = 1 mole of Na = 1 mole of Cl
hence 0.78 mol of NaCl = 0.78 mol of Na = 0.78 mol of Cl.
mass of Na = 0.78 × 23
= 17.94 grams
mass of Cl = 0.78 × 35.5
= 27.69 grams
The mass of the sodium and chlorine gas taken for the reaction was 17.92 grams and 27.73 grams respectively.
What is sodium chloride?Sodium chloride is an ionic compound in which the sodium (Na⁺) and chloride (Cl⁻) ions are present in a ratio of 1 : 1. It is commonly known as table salt or halite.
Sodium and chlorine react with each other to generate a substance that is familiar to everybody around the globe which is sodium chloride.
2Na (s) + Cl₂ (g) [tex]\longrightarrow[/tex] 2NaCl (s)
The atomic mass of the sodium (Na) = 23 g/mol
The atomic mass of chlorine,(Cl) = 35.5 g/mol
The molar mass of the sodium chloride (NaCl) = 58.5 g/mol
Given, the mass of the NaCl formed = 45.6 g
If 117 g NaCl formed from sodium = 2× 23 g
Then 45.6 NaCl will be formed from Na = 17.92 g
If 117 g NaCl formed from chlorine = 2× 35.5 g
45.6 NaCl will be formed from chlorine = 2× 35.5 ×45.7/117 = 27.73 g
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If 8.500 g of sodium nitrate and 7.500 g of potassium chloride are dissolved in 25.0 mL of water and heated to 80°C no solid Watermain. Using these amounts of potassium chloride and sodium nitrate, calculate the theoretical number of grams of sodium chloride and potassium nitrate that could be formed.
Answer:
Zero grams of NaCl & KNO₃ ... The reagents mixed in aqueous solution would not produce products as no driving force is present; i.e., no precipitate, weak electrolyte or gas decomposition product will form.
Explanation:
NaNO₃(aq) + KCl(aq) => (theoritically) NaCl(aq) + KNO₃(aq)
However all chloride salts from metathesis rxns remain soluble and 100% ionized except for halide derivatives of Hg⁺², Ag⁺ & Pb⁺₂. Further, all NO₃⁻ salt derivatives also remain soluble and 100% ionized.
Technically, metathesis reactions (also known as double replacement rxns) depend upon the formation of a 'driving force' that leaves the reaction system in the form of a precipitate, weak electrolyte (weak acid or weak base) or a gas decomposition product. So, the reaction in this case should be as follows:
NaNO₃(aq) + KCl(aq) => No Reaction
Which of these is an example of an ecosystem service?
A. A mangrove forest protects a coastal village from erosion.
B. A farmer uses non-chemical means to control pests and weeds.
C. A city enacts a law to protect a local lake from runoff pollution.
D. After closing a mine, a company adds soil and plants native grasses in the area.
someone help me asap.
Answer:
A
Explanation:
All of the other options involve cities, farmers, or companies. Those aren't natural occurrences, so A is the answer. The mangroves protect the village without anything being modified about that environment.
Which phrase describes a situation in which all the forces are balanced?
O A. A student slipping on icy ground
O B. A student leaning against a brick wall
O C. A student walking across a room
D. A student diving into a swimming pool
Answer:
B
Explanation:
I sacrificed my grade for pakistan.
Am I really stupid for not knowing this ;-;
Answer:
A. Gases;nonreactive
Explanation:
No ur not stupid, lol hope this helps!
Answer:
other dude is right also you aren't another thing sorry I be late
Explanation:
The molecular formula of butane is C4H10C4H10. It is obtained from petroleum and is used commonly in LPG (Liquefied Petroleum Gas) cylinders (a common source of cooking gas). It has two arrangements of carbon atoms: a straight chain and a branched chain.
Required:
a. Using this information, draw the structure of the tertiary butyl radical that will form upon removal of a hydrogen atom.
b. Draw the molecule on the canvas by choosing buttons from the Tools (for bonds), Atoms, and Advanced Template toolbars.
Answer:
Explanation:
Butane is an alkane with the molecular formula C₄H₁₀.
(a) It has two structural isomers (n-butane and 2-methylpropane) shown below
H H H H
| | | |
H - C - C - C - C - H
| | | |
H H H H
The structure above is n-butane
H CH₃ H
| | |
H - C - C - C - H
| | |
H H H
The structure above is 2-methylpropane and can also be referred to be a tertiary butane because the central carbon atom has 3 methyl groups attached to it as shown below.
CH₃
|
H₃C - C - CH₃
|
H
Hence, the structure of a tertiary butyl radical after loss/removal of a hydrogen atom will be
CH₃
|
H₃C - C⁻ - CH₃
NOTE: It should be noted that the central carbon becomes negatively charged after the loss of the hydrogen atom
(b) This is the practical part of the structure drawn above. The last structure illustrated above can be drawn on the canvas with the instruction provided in the question.
1. What fraction of the elements on the periodic table are metals?
Answer:
About 80% of the elements on the periodic table are metals.
Explanation:
10. Bands of rock on the seafloor showing alternating magnetic orientation indicate Earth's magnetic field has ____.
a. reversed itself in the past
b. weakened
c. becomes stronger
d. remained the same
Answer:
The answer is Reverse Itself In The Past
How would you convert 500cc of 2M H2SO4 into g/l?
Answer:
Number of replacable H
+
ions in H
2
SO
4
=n=2
Normality =n× Molarity=2×2=4 N
1. Which macromolecules would you need if... you need a quick boost of
energy?
Answer:
[tex]\boxed {\tt Carbohydrate \ or \ monosaccharides}[/tex]
Explanation:
There are 4 main types of macromolecules: lipids, proteins, carbohydrates, and nucleic acids.
If you are looking for some quick energy, the best choice is carbohydrates. Carbohydrates are the easiest for the body to break down and turn into ATP/energy.
There are also different types of carbohydrates. If you want a more specific answer, monosaccharides is the best answer. They are the simplest sugars. Also, glucose is a monosaccharide, and it shows up directly in the cellular respiration formula. If glucose is consumed, the body doesn't have to break it down before starting respiration.
What is the density of a piece of cement has a mass of 8.76 g and volume of 3.07 cm^3?
Answer:
2.85g/cm^3
Explanation:
density = mass/volume
density=8.76g/3.07cm^3= 2.85g/cm^3
Answer:
The answer is 2.85 g/cm³Explanation:
The density of a substance can be found by using the formula
[tex]density = \frac{mass}{volume} \\ [/tex]
From the question we have
[tex]density = \frac{8.76}{3.07} \\ = 2.85342019...[/tex]
We have the final answer as
2.85 g/cm³Hope this helps you
C + H2O → CO + H2
What is the starting substance?
Answer:
Explanation:
Carbon and water = carbon dioxide and hydrogen
I need help with the question they are asking
Answer:
i wish i could help but people are around me
Explanation:
АМА
H
+
O
HGS
-O-H
H
N-H
H
Single Bond
AMA
H
+
0
-0-H
H
Single Bond
Carbon burns with oxygen to produce carbon dioxide gas. Which of these shows the correct chemical reaction? C + O2 → CO2 C, O, CO2 C + O = CO2 CO2 = C + O
Answer:
c+o2=co2
Explanation:
balanced reaction it is correct
Answer:
C + O2 → CO2
Explanation:
i took the test and got it right
Which of the following are products of the light-dependent reactions of photosynthesis that are utilized in the light-independent reactions?
ATP and NADPH
water and oxygen
oxygen and glucose
carbon dioxide and glucose
Answer:
[tex]\boxed {\tt Oxygen \ and \ glucose}[/tex]
Explanation:
The photosynthesis equation is:
energy+6CO₂+6H₂O--> C₆H₁₂O₆+6O₂
The reactants are light energy, carbon dioxide, and water. The products are glucose and oxygen.
The products of photosynthesis become the products of the light-independent reaction called cellular respiration, which creates useable energy. Therefore, the correct answer is oxygen and glucose.