Answer: to find a cure for the common cold to produce insulin for diabetics
Explanation: It has helped many people
I NEED HELP PLEASE, THANKS! :)
A manufacturing company is trying to produce a lightweight but strong cart for use by home gardeners. Which metal—titanium (Ti), iron (Fe), or zinc (Zn)—would be the best for this application and why?
Answer:
Titanium; lowest density
Explanation:
The cart would use the same volume of metal, no matter which one it was made of.
If weight were the only consideration, the company would choose the metal with the lowest density.
The values I find for the metals are
Ti 4.5 g/cm³
Fe 7.9 g/cm³
Zn 7.1 g/cm³
Titanium would be the best metal for this application.
Answer:
Titanium would be the best metal for this application because it is a low density metal that is still strong and ductile
Explanation:
__C7H16+ ___O2=
CO2 + H20 how to balance this equation
Answer:
C7H16 + 11O2 = 7CO2 + 8H2O
Explanation:
Start by balancing the C and H in C7H16 by adding the coefficient of 7 for CO2 because there are 7 C's in C7H16. Similarly, since there are 16 H's in C7H16, balance it by adding the coefficient of 8 to the H2O, which will result in 16 H's.
Finally, add up the O's on the right side and balance it by adding the appropriate coefficient on the O2. On the right, there are 22 O's, so balance the equation by adding the coefficient of 11 on the left for the O2.
Explain why covering something with a blanket can put out a fire
Answer:
No oxygen
Explanation:
when something is covered in a blanket it prevents the fire from being able to have any oxygen
Answer:
Its called smothering the fire
Explanation:
A fire needs three things to burn always: fuel, oxygen, and a heat source. Eventually the heat source will not be an issue, but the oxygen and fuel is. If the fire is small enough throwing a blanket can quite smother it. What happens is it cuts off the oxygen supply the fire needs long enough for it to die out.
Why is John Dalton known as the originator of atomic theory?
Answer:
he thought of atoms first
Answer:
He was the first to be the one to propose that matter is made out of atoms. He also proved that the atoms are divisible in nature.
Allicin is the compound responsible for the characteristic smell of Garlic. An analysis of the compound gives the following percent composition by mass; C = 44.4 percent, H = 6.21 percent. S = 39.5 percent, O = 9086 percent. Calculate its empirical formula. What is its molecular formula given that its molar mass is about 162 g?
Answer:
The empirical formula is same as the molecular formula = C6H10S2O
Explanation:
we start by dividing the percentage of each of the elements by their atomic mass
Carbon = 44.4/12 = 3.7
Hydrogen = 6.21/1 = 6.21
Sulphur = 39.5/32 = 1.234375
oxygen = 9.89/16 = 0.618125
That of oxygen is smallest so we divide all by that of oxygen
C = 3.7 / 0.618125 = 6
H = 6.21/ 0.618125 = 10
S = 1.234375/ 0.618125 = 2
Automatically, oxygen is 1
So the empirical formula is;
C6H10S2O
Let’s get its molecular formula. We multiply each of the subscript by the number;
(72 + 10 + 64 + 16)n= 162
162n = 162
n = 1
So the molecular formula is same as the empirical formula
Why does the presence of lone pairs contribute to the polarity of a water molecule
Explanation:
They allow the bonds between oxygen and hydrogen to be single. They increase the partial positive charge on the oxygen atom. They counter the uneven pull on electrons between the atoms.
what is pyruvate converted to
Answer:
gold
Explanation:
Why does the structure of the plasma membrane make this type of transport necessary for fluids
Answer: because the phospholipid bilayer formed by these interactions makes a good barrier between the interior and exterior of the cell, because water and other polar or charged substances cannot easily cross the hydrophobic core of the membrane.
Explanation:
WILL GIVE BRAINLIEST FOR CORRECT ANSWERS W/ EXPLANATION
PLEASE HELP...
Ethyl acetate is a sweet-smelling solvent used in varnishes and fingernail polish remover. It is produced industrially by heating acetic acid and ethanol
together in the presence of sulfuric acid, which is added to speed up the
reaction. The ethyl acetate is distilled off as it is formed. The equation for the
process is as follows.
CH3COOH + CH3CH2OH --> CH3COOCH2CH3 + H2O
Determine the percentage yield in the following cases:
a. 68.3 g of ethyl acetate should be produced but only 43.9 g is recovered.
b. 0.0419 mol of ethyl acetate is produced but 0.0722 mol is expected. (Hint:
Percentage yield can also be calculated by dividing the actual yield in moles
by the theoretical yield in moles.)
c. 4.29 mol of ethanol is reacted with excess acetic acid, but only 2.98 mol of
ethyl acetate is produced.
d. A mixture of 0.58 mol ethanol and 0.82 mol acetic acid is reacted and 0.46
mol ethyl acetate is produced. (Hint: What is the limiting reactant?)
Answer:
The percentage yields are as follows :
a) 64.28%
b) 58.03%
c) 69.46%
d) 79.31%
Explanation:
The percentage yield is the ratio of the actual yield of a product to the expected or theoretical yield expressed as a percentage.
Percent yield = actual yield/theoretical yield x 100%
a) from the question, expected yield is 68.3 g whilst the actual yield is 43.9 g
therefore,
Percentage yield = 43.9 g/68.3 g x 100%
= 0.64275 x 100%
= 64.28%
b) From the question, expected yield is 0.0722 mol while the actual yield is 0.0419 mol. Therefore
Percentage yield = 0.0419 /0.0722 x 100%
= 0.58033 x 100%
= 58.03%
c) A limiting reactant is the reactant is is completely used in a recation to form a product. That is, it is the reactant that is not in excess.
From the equation of the reaction :
CH3COOH + CH3CH2OH --> CH3COOCH2CH3 + H2O
1 mole of ethanol reacts with 1 mole of acetic acid to give 1 mole of ethyl acetate.
From the question, ethanol is the limiting reactant because it is not in excess. Hence,
4.29 mole of ethanol should produce 4.29 mole of ethyl acetate (expected yield).
However only 2.98 mol of ethyl acetate is produced (actual yield)
Percentage yield = 2.98mol/4.29 mol x 100%
= 0.69463 x 100%
= 69.46%
d) From the question, acetic acid is in excess hence ethanol is the limiting reactant
therefore from the equation of the reaction:
1 mole of ethanol reacts with 1 mole of acetic acid to give 1 mole of ethyl acetate.
0,58 mol of ethanol should produce 0.58 mol of ethyl acetate (expected yield)
But 0.46 mol of ethyl acetae was produced (actual yield)
Percentage yield = 0.46mol /0.58 mol x 100%
= 0.79310 x 100%
= 79.31%
Does the conductivity increase or decrease?
O It increases at first, then decreases.
O It continuously decreases
O It continuously increases
O lt decreases at first, then increases
Answer:
It continuously decreases.
Explanation:
the thermal motion makes the electrons to collide and disturb the free flow. Thus, conductivity is decreased.
5.6 × 1012 / 3.5 × 109 = A × 10B
Answer:
B= 17649.28/A
Explanation:
What is the normal boiling point of of a solution containing 64.5g of non volatile quinoline ( MW 129 ) in 500 g of benzene when the normal boiling point is 80.10 and KB = 2.50
Answer:
THE NORMAL BOILING POINT OF A SOLUTION CONTAINING 64.5 g OF QUINOLINE IN 500 g OF BENZENE IS 82.6 C
Explanation:
Boiling point = old boiling point + molarity * boiling point constant (Kb)
First, you calculate the number of moles of quinoline in the solution
number of moles = mass / molar mass
Since the molar mass of quinoline has been given as 129 g/mol
number of moles = 64.5 g / 129 g/mol
number of moles = 0.5 moles.
Next is to determine the molarity:
molarity = number of moles of solute / kilogram of solvent
molarity = 0.5 moles / 500/1000 kg
molarity = 0.5 / 0.5
molarity = 1 M
The new boiling point can then be calculated using the formula:
B. P = old B.P + Kb * molarity
B.P = 80.10 + 2.50 * 1
B.P = 80.10 + 2.50
B.P = 82.6 degree celsius
Of the choices below, which one is not an ionic compound?
A) PCl5
B) MoCl6
C) RbCl
D) PbCl2
E) NaCl
Answer: [tex]PCl_5[/tex] is not an ionic compound.
Explanation:
An ionic compound is defined as the compound which is formed when electron gets transferred from one atom to another atom. The cation is formed by loss of electrons by metals and anions are formed by gain of electrons by non metals.
Thus [tex]MoCl_6[/tex], [tex]RbCl[/tex], [tex]PbCl_2[/tex] and [tex]NaCl[/tex] are all ionic compounds.
Covalent compound is defined as the compound which is formed by the sharing of electrons between the atoms forming a compound. These are usually formed when two non-metals react.
Thus [tex]PCl_5[/tex] is a covalent compound as both Phosphorous and chlorine are non metals.
PCl₅ is not an ionic compound. Ionic or electrovalent compounds are formed
through the transfer of electrons in a chemical reaction. Metals and non-
metals mostly form ionic compounds.
Covalent bonding on the other involves the sharing of electrons between
two elements. Non-metals are mostly involved in this type of reaction.
PCl₅ possesses a covalent bond and not ionic as electrons are shared
between two non metals which are phosphorus and chlorine.
Read more on https://brainly.com/question/957239
is bleached water safe for drinking???
Answer:
NO most of the time
Explanation:
I hope this is for school and not personal reasons. Bleach will kill you if drank plain, if it's diluted a little it may not be fatal but can still greatly harm your organs. If it is diluted extremely it is used for cleaning tap water and is perfectly fine.
Just to be on the safe side, I want you to know there is always help, and if you need someone to talk or text this is the number for the National Su1c1de Hotline and it is free and available if you are ever feeling like self harm is the only way out:
800 273 8255
Which is one way that topographic maps are different from other maps?
Answer:
The answer is A. Unlike other maps, topographic maps indicate man-made and natural landforms.
Explanation: Took the test and got 100% Edg. 2020
Answer:
A)Unlike other maps, topographic maps indicate man-made and natural landforms.
Explanation:
Which is one way that waves erode coastlines?
Answer:
Four main processes erode the destructive waves; hydraulic action, compression, abrasion and attrition. Hydraulic Action is the sheer force of water crashing off the coastline causing the material to dislodge and be carried away by the sea.
Answer:
a
Explanation:
A.
B.
C.
D.
what could be the correct answer? Help me please
Answer:
A
Explanation:
Answer:
a
Explanation:
A catalyst can only be used once.
True
False
Answer:
False
Explanation:
Catalysts are reusable because they keep the chemical reactions moving without being consumed.
Q2. Which of these is a mixture?
1.chlorine
2.sodium chloride solution
3.sodium
4,sodium chloride
What is meant by “normal” when you are asked for normal boiling and melting points?
Answer:
Normal boiling point is the temperature at which a liquid boils at 1 atmosphere of pressure.
Explanation:
Given the following chemical equation at equilibrium: H2(g) + I2(g) ↔2HI(g) + heat. If the temperature is raised, in what direction will the equilibrium shift?
Answer: The reaction will shift in left or backward direction.
Explanation:
Any change in the equilibrium is studied on the basis of Le-Chatelier's principle. This principle states that if there is any change in the variables of the reaction, the equilibrium will shift in the direction to minimize the effect.
For the given equation:
[tex]H_2(g)+I_2(g)\rightleftharpoons 2HI(g)+heat[/tex]
As the given reaction is exothermic as the heat is released in the reaction. When the temperature is raised , the reaction will shift in a direction where temperature is decreasing and that is the reverse reaction which is endothermic in nature.
Thus the reaction will shift in left or backward direction.
Which evidence would most strongly indicate that a chemical change is
taking place?
A. Fizzing
B. Changing shape
C. Breaking
D. Changing state
Two boxes need to be moved into storage. Jamal and Jude each want to move a box. The force of gravity on both the boxes is 50 N. Jamal is lifting with a force of 60 N, and Jude is lifting with a force of 45 N. Which best describes the movement of the boxes? Jamal moved his box to storage, but Jude could not move his. Jamal and Jude can successfully move each box into storage. Jamal could not move his box to storage, but Jude could. Neither Jamal nor Jude could move the boxes into storage.
Answer: 80
Explanation:
Answer:
Jamal moved his box to storage, but Jude could not move his.
Explanation:
The force they exert needs to be higher than the force of gravity in order for them to move the boxes. Jamal's force is 60N, which is 10N above the force of gravity on the box, which is 50N. However, Jude's force is only 45N and that is lower than 50N, so he won't be able to move the box while Jamal can.
An aluminum can holds 350 mL of gas at 0 C and 1.0 atm. what is the new volume if the can is heated to 10 C and the pressure inside the can rises to 75 atm?
Answer:
Final volume of the gas is 4.837mL
Explanation:
Initial volume (V1) = 350mL = 0.35L
Initial temperature (T1) = 0°C = (0 + 273.15)k = 273.15k
Initial pressure (P1) = 1.0atm
Final volume (V2) = ?
Final temperature (T2) = 10°C = (10 + 273.15)k = 283.15K
Final pressure (P2) = 75atm
To solve this question, we'll have to use combined gas equation which is the combination of all gas law I.e Charle's laws, Boyle's law, Pressure law etc.
According to combined gas equation,
(P1 × V1) / T1 = (P2 × V2) / T2
Make V2 the subject of formula,
V2 = (P1 × V1 × T2) / (P2 × T1)
V2 = (1.0 × 0.35 × 283.15) / (75 × 273.15)
V2 = 99.1025 / 20,486.25
V2 = 0.004837L
V2 = 4.837mL
The final volume of the gas is 4.837mL
Answer:
4.84mL
Explanation:
Step 1:
Data obtained from the question. This include the following:
Initial volume (V1) = 350mL
Initial temperature (T1) = 0°C
Initial pressure (P1) = 1atm
Final temperature (T2) = 10°C
Final pressure (P2) = 75atm
Final volume (V2) =...?
Step 2:
Conversion of celsius temperature to Kelvin temperature.
This can be achieved by using the formula below:
T(K) = T (°C) + 273
Initial temperature (T1) = 0°C
Initial temperature (T1) = 0°C + 273 = 273K
Final temperature (T2) = 10°C
Final temperature (T2) = 10°C + 273 = 283K
Step 3:
Determination of the new volume.
The new volume can be obtained by using the general gas equation as follow:
P1V1/T1 = P2V2/T2
1 x 350/273 = 75 x V2/283
Cross multiply
273 x 75 x V2 = 1 x 350 x 283
Divide both side by 273 x 75
V2 = (1 x 350 x 283) / (273 x 75)
V2 = 4.84mL
Therefore, the new volume is 4.84mL
What does the symbol (–Delta.Hfus) indicate in a phase change?
Answer:
changes from a solid to a liquid
Explanation:
C- A solid is being formed
Since the delta is negative, this indicates that a substance is transforming from a liquid state to a solid state. This best corresponds with C- A solid is being formed.
Read the following statements carefully: X: It is a thick black coloured liquid which is obtained from coal.Y: It was used earlier in railway engines to produce steam to run trains.Z : It is used to run heavy vehicles such as buses, trucks, tractors, etc.X, Y and Z respectively are
Options are not given in the question. The complete question is as follows:
Read the following statements carefully: X: It is a thick black coloured liquid which is obtained from coal.Y: It was used earlier in railway engines to produce steam to run trains.Z : It is used to run heavy vehicles such as buses, trucks, tractors, etc.X, Y and Z respectively are
A. a. Coal tar b. Coal c. Diesel
B. a. Coal b. Paraffin wax c. Petrol
C. a. Coke b. Coal tar c. Kerosene
D. a. Coke b. Coal c. Coal tar
Answer:
A. a. Coal tar b. Coal c. Diesel
Explanation:
Coal Tar is a thick black or dark brown colored liquid obtained from coal. Coal Tar consists of hydrocarbons and free carbon extracted from coal using a process of destructive distillation. So, X is coal tar.
Earlier coal was used to produce steam to run steam engine trains. Air flows are allowed to burn coal hotter, then the hot coal turns water to steam and helps in the locomotive steam engine to run. So, Y is coal.
Deisel is used to run heavy vehicles such as buses, trucks, tractors, etc. because diesel burns at slow speed and produces a higher torque that can move heavy automobiles. So, Z is deisel.
Hence, the correct option is A.
What can happen when tectonic plates move a few centimeters?
Answer:
whole continents can move.
How do greenhouse gases such as CO2 and N2O contribute to an increase in Earth’s atmospheric temperature?
A.
Greenhouse gases interact with infrared photons and reflect them back to Earth’s surface.
B.
Greenhouse gases chemically react with one another, releasing heat in the process.
C.
Greenhouse gases agitate visible light photons, increasing the photons’ temperature and motion energy.
D.
Greenhouse gases generate internal heat through radioactive decay, similar to the core of Earth.
Answer:
The answer is A
Explanation:
The earth naturally maintains the heat energy balance by absorbing a sufficient amount of sunlight energy by the terrestrial land and then reverting back the excess sunlight energy back to the space. The increase in abundance of greenhouse gases in the atmosphere results in absorption of sunlight energy which contains infrared photons this is responsible for increasing the global temperature levels hence, responsible for global warming. These infrared photons are reflected to the earth surface instead of sending back to the space. This is responsible for disturbing the heat balance.
Greenhouse gases interact with infrared photons and reflect them back to earth’s surface, hence option A is correct.
How does greenhouse gases rise in earth’s atmosphere?The burning of fossil fuels, logging of forests, and raising of livestock all have a rising impact on the climate and temperature of the planet.
This increases the greenhouse effect and causes global warming by adding a significant amount of greenhouse gases to those that are already present in the atmosphere.
The earth naturally maintains the balance of heat energy by receiving enough solar energy through the terrestrial land and then returning any excess energy to space.
Therefore, greenhouse gases such as CO₂ and N₂O interact with infrared photons and reflect them back to earth’s surface.
Learn more about greenhouse gases, here:
https://brainly.com/question/14131369
#SPJ5
What is the total energy change for the following reaction: H2 + I2 -> 2HI?
Given:
H-H bond: 436 kJ/mol
I-I bond: 151 kJ/mol
H-I bond: 297 kJ/mol
A. +7 kJ/mol
B. +297 kJ/mol
C. -290 kJ/mol
D. -7 kJ/mol
Energy change is the conversion of the energy stored in reactants to products. In the reaction between hydrogen and iodine, the energy change is -7 kJ/mol. Thus, option D is correct.
What is total energy change?Total energy change is the conversion of the energy from a substance to another when the reactant undergoes modification to produce a product.
The reaction is given as,
H₂ + I₂ → 2HI
In the reaction, the bonds between H-H and I-I are broken to release energy that produces two H-I bonds as the product.
Given,
H-H bond = 436 kJ/mol
I-I bond = 151 kJ/mol
H-I bond = 297 kJ/mol
So, 436 kJ/mol + 151 kJ/mol - 2x297 kJ/mol = -7 kJ/mol
Therefore, -7 kJ/mol is the total energy change in the reaction involving hydrogen and iodine.
Learn more about total energy change here:
https://brainly.com/question/14769257
#SPJ5
Describe how a polyploid is formed
Answer:
ExpPolyploidy is the heritable condition of possessing more than two complete sets of chromosomes. Polyploids are common among plants, as well as among certain groups of fish and amphibians. For instance, some salamanders, frogs, and leeches are polyploids. Many of these polyploid organisms are fit and well-adapted to their environments. In fact, recent findings in genome research indicate that many species that are currently diploid, including humans, were derived from polyploid ancestors (Van de Peer & Meyer, 2005). These species that have experienced ancient genome duplications and then genome reduction are referred to as paleopolyploids. This article discusses the mechanisms underlying polyploidy, and both the advantages and disadvantages of having multiple sets of chromosomes.
Mechanisms of Polyploidy
This diagram shows several pathways by which diploid species can transition to polyploid species and polyploid species can transition to diploid species. Each species is represented by an oval containing two or more colored circles. Each colored circle represents a complete set of chromosomes.
View Full-Size ImageFigure 1
Figure Detail
How does an organism become polyploid? Polyploids arise when a rare mitotic or meiotic catastrophe, such as nondisjunction, causes the formation of gametes that have a complete set of duplicate chromosomes. Diploid gametes are frequently formed in this way. When a diploid gamete fuses with a haploid gamete, a triploid zygote forms, although these triploids are generally unstable and can often be sterile. If a diploid gamete fuses with another diploid gamete, however, this gives rise to a tetraploid zygote, which is potentially stable. Many types of polyploids are found in nature, including tetraploids (four sets of chromosomes), hexaploids (six sets of chromosomes), and other chromosome-pair multiples