Answer:
cotton
Explanation:
which is typically spun into fine yarn for mechanical weaving or knitting into cloth.
physical and chemical changes occur in digestion. What is an example of an physical change in digestion
teeth chewing food
acid mixing with food
saliva mixing with food
enzymes mixing with food
Answer:
teeth chewing food
Explanation:
When teeth chews food it change its state from hard solid to fine substance that can be easily digested by the body i guess
For the diprotic weak acid H2A, a1=3.2×10−6 and a2=6.1×10−9 .
What is the pH of a 0.0750 M solution of H2A ?
What are the equilibrium concentrations of H2A and A2− in this solution?
In the first dissociation of H2A:
molarity H2A(aq)↔ (HA)^-(aq) + H^+(aq)
initial 0.05 m 0 m 0 m
change -x +x +x
equilibrium 0.05-x x x
we can neglect X in [H2A] as it so small compared to the 0.05
so by substitution in Ka equation:
Ka1 = [HA][H] / [H2A]
2.2x10^-6 = X^2/0.05
X = √(2.2x10^-6)*(0.05)= 1.1x10^-7
X= 3.32x10^-4 m
∴ [H2A] = 0.05 - 3.32x10^-4 = 0.0497 m
[HA] = 3.32x10^-4 m
[H] = 3.32x10^-4 m
the second dissociation of H2A: when ka2 = 8.2x10^-9
HA-(aq) ↔ A^2- (aq) + H+(aq)
at equilibrium 3.32x10^-4 y 3.32x10^-4
Ka2 = [H+][A^2-] / [HA]
8.2x10^-9 = Y(3.32x10^-4)/(3.32x10^-4)
∴y = 8.2x10^-9 m
∴[A] = 8.2x10^-9 m
PH= -㏒[H+]
= -㏒(3.32x10^-4)= 3.479
[A]=8.2x10^-9 m
[H2A] = 0.0497 ≈ 0.05 m
HELP PLEASE I WILL GIVE BRAINLIEST PLEASE HELP ME
Explain the law of conservation of mass. Give an example of how mass is conserved using numbers to justify your answer.
Answer:
The law of conservation of mass states that matter cannot be created or destroyed in a chemical reaction.
For example, when wood burns, the mass of the soot, ashes, and gases equals the original mass of the charcoal and the oxygen when it first reacted. So the mass of the product equals the mass of the reactant.
Another example, solar panels don't create solar energy. They harness energy from the sun and transform it into another type of energy (electricity).
A student experimentally determines the gas law constant, R, by reacting a small piece of magnesium with excess hydrochloric acid and then collecting the hydrogen gas over water in a eudiometer. Based on experimentally collected data, the student calculates R to equal 0.0832
Due to errors in volume and moles measurement by the student, the true value of the molar gas constant is less than the obtained value.
The Percent error is 1.39%
What is percent error?Percent error is defined as the ratio of error and true value of a measurement expressed as a percentage.
Percent error = (error/true value) × 100%Error = |true value - measured value|
The error in the students measurement = |0.08206 - 0.0832|
Error = 0.00114
Percent error = (0.00114/0.08206) × 100%
Percent error = 1.39%
The formula to determine the molar gas constant R is given below:
[tex]R = \frac{PV}{nT}[/tex]
Since the student value is higher than the true value, the possible sources of error include:
The student student does not equilibrate the water levels within the eudiometer and the beaker at the end of the reaction resulting in increased volumeThe student does not clean the zinc with sand paper, thus the number of moles of hydrogen gas produced is less than the actual value.Therefore, the true value of the molar gas constant is less than the obtained value.
Learn more about molar gas constant R at: https://brainly.com/question/1405354
Describe the experiment that Chadwick conducted which led to his discovery of the neutron.
Answer:
James Chadwick conducted an experiment where he assailed the element Beryllium with alpha particles that came from the radioactive decay of Polunium. The experiment results showed highly penetrating radiation emitted from the Beryllium. In this, Chadwick proposed that radiation consisted of uncharged particles, which were later founded as neutrons.
A mixture of two or more metals is called: A) Mixture B) Compound C) solution D) alloy
Answer:
C
Explanation:
Mixture of 2 or more metals is a compound
example is water which is made up of hydrogen and oxygen.
buna, am nevoie de un site de facut proiecte
Answer:
translation to English please
plzz help me cant remember the parts of the flower.
A is the petal and b is the leaf. I think.
Which of the following is an example of climate?
A. The polar regions have long winters and short, cool summers.
B. Humidity levels are high today.
C. Canada experienced an unusually warm summer this year.
D. Tornados formed across Oklahoma yesterday.
Answer:
A. The polar regions have long winters and short, cool summers.
Explanation:
Climate is location based, however is over long periods of time, so Canada would not be considered because it is only 1 summer
agine that you are just outside the International Space Station (ISS) orbiting Earth, working in space. You brought your speaker with you so you could listen to some music while you work. You find the right song, and you hit play. What do you hear? Write your response below in complete sentences. 3) Include the answers to these questions in your response: • Would you hear your music? • Why or why not?
Answer:
There is no atmosphere outside the space station, so there is nothing to vibrate, therefor there is no sound.you better install your earphones in your space suit.
Explanation:
Imagine that you are just outside the International Space Station (ISS) orbiting Earth, working in space. You brought your speaker with you so you could listen to some music while you work. You find the right song, and you hit play. What do you hear? Write your response below in complete sentences.
Include the answers to these questions in your response: •
Would you hear your music? •
Why or why not?
You need matter that can vibrate and finally vibrate your ear drum in order to transmit sound waves. that you hear
There is no atmosphere outside the space station, so there is nothing to vibrate, therefor there is no sound.you better install your earphones in your space suit.
You will hear no music as there is no sound in the space because there are no molecules to vibrate.
Why no sound in the space?Sound is generally considered a form of energy that consists of mechanical waves which travel in a medium. Sound is produced by a vibrating body which generates a disturbance in the medium and the medium helps to propagate the sound.
The medium of sound transmission is air where the molecules in the air are in the form of longitudinal waves. The vibrating body generates a disturbance in the rarefaction and compression of waves. The disturbance of the particles of the surrounding medium produces sound.
Sound always requires a medium to be traveled and reach its destination. As space does not have any medium for sound to generate disturbance. Space has a vacuum due to which sound cannot be heard in space.
Therefore, you will hear no music when you play a song in the space.
Learn more about sound, here:
https://brainly.com/question/14109969
#SPJ2
*1. The internal energy with a system associated with the motion of particles and that can be added to a substance is called_____.
A. Thermal energy
B. Electrostatic forces
C. Temperature
D. Kinetic energy
•
•
•
*2. Which statement describes the effect of adding more energy to a system, assuming a phase change does not occur?
A. The particles within the system will have greater motion, and the temperature will decrease.
B. The particles within the system will have greater motion, and the temperature will increase.
C. The particles within the system will have less motion, and the temperature will increase.
D. The particles within the system will have less motion, and the temperature will decrease.
•
•
•
*3. Which statement correctly describes how attractions that hold particles break?
A. Attractions due to electrostatic forces. When particles have low enough energy, these forces can no longer keep particles together.
B. Attractions due to gravitational forces. When particles have low enough energy, these forces can no longer keep particles together.
C. Attractions due to gravitational forces. When particles move fast enough, these forces can no longer keep particles together.
D. Attractions due to electrostatic forces. When particles move fast enough, these forces can no longer keep particles together.
•
•
•
*4. Which statement explains why a rubber band analogy is not a perfect comparison for bonds in a substance when considering phase changes?
A. For a phase change from liquid to gas, the bonds break completely and particles can move independently of each other.
B. For a phase change from liquid to gas, the bonds do not break completely and the particles can still slide past each other.
C. For a phase change from solid to liquid, the bonds break completely and particles can move independently of each other.
D. For a phase change from solid to liquid, the bonds do not break completely in the particles can still slide past each other.
•
•
•
*5. The boiling point of benzene is 80°C. Which pair of samples will have the same average kinetic energy as benzene molecules?
A. Two samples of liquid benzene, one at 70°C in the other at 80°C.
B. A sample of liquid benzene at 70°C and a sample of gaseous benzene at 90°C.
C. Two samples of gaseous benzene, one at 80°C in the other at 90°C.
D. A sample of liquid benzene at 80°C and a sample of gaseous benzene at 80°C.
Answer:
1. thermal energy
2. the particles within the system will have greater motion, and the temp will increase.
3. attractions occur due to electrostatic forces. when particles move fast enough, these forces can no longer keep particles together.
4. for a phase change from a solid to liquid, the bonds do not break completely and particles call still slide past each other.
5. a sample of liquid benzene at 80°C and a sample of gaseous benzene at 80°C
Explanation:
hope this helps
Temperature is a measure of the average kinetic energy of molecules.
The particles of a substance are in constant random motion. As more thermal energy is added to the particles, the motion of the particles increases. If more energy is added to a system during phase change, the particles within the system will have greater motion, and the temperature will increase.
Attractions between particles is greater when the kinetic energy of molecules decreases. Therefore, a statement that correctly describes how attractions that hold particles break is; "attractions due to electrostatic forces. When particles move fast enough, these forces can no longer keep particles together."
The rubber analogy is commonly used to describe covalent bonds where stretching of bonds occur. This analogy is not apt in describing phase changes because for a phase change from a solid to liquid, the bonds do not break completely and particles call still slide past each other.
The average kinetic energy of molecules depend on temperature hence a sample of liquid benzene at 80°C and a sample of gaseous benzene at 80°C will have the same average kinetic energy.
Learn more: https://brainly.com/question/865531?
The heat of combustion of propane, C3H8 (g) is -2057 kJ/mol. What would be the enthalpy change if enough propane was burned to give off 12 moles of carbon dioxide gas
Considering the reaction stoichiometry, the enthalpy change if enough propane was burned to give off 12 moles of carbon dioxide gas is 8228 kJ.
The balanced reaction is:
C₃H₈(g) + 5 O₂(g) → 3 CO₂(g) + 4 H₂O(l)
The heat of combustion of propane, C₃H₈, is -2057 kJ/mol. This is, 2057 kJ is released for every 1 mol C₃H₈.
So to determine the enthalpy change if enough propane was burned to emit 12 moles of carbon dioxide, you must take into account the stoichiometry of the reaction.
By reaction stoichiometry (that is, the relationship between the amount of reagents and products in a chemical reaction), the following amounts of moles of each compound participate in the reaction:
C₃H₈: 1 mole O₂: 5 moles CO₂: 3 moles H₂O: 4 molesThen you can apply the following rule of three: if by stoichiometry 3 moles of CO₂ are produced by 1 mole of C₃H₈, 12 moles of CO₂ are produced by how many moles of C₃H₈?
[tex]amount of moles of C_{3} H_{8} =\frac{12 moles of CO_{2}x1 mole of C_{3} H_{8} }{3 moles of CO_{2}}[/tex]
amount of moles of C₃H₈= 4 moles
So to determine the enthalpy change, you can apply the following rule of three: If for each mole of C₃H₈ 2057 kJ are released, for 4 moles of C₃H₈ how much heat is released?
[tex]Heat released=\frac{4 molesx2057 kJ}{1 mole}[/tex]
Heat released= 8228 kJ
The enthalpy change if enough propane was burned to give off 12 moles of carbon dioxide gas is 8228 kJ.
Learn more:
https://brainly.com/question/10936616?referrer=searchResultsbrainly.com/question/16487206?referrer=searchResults brainly.com/question/14446695?referrer=searchResults brainly.com/question/11564309?referrer=searchResults brainly.com/question/4025026?referrer=searchResults brainly.com/question/18650135?referrer=searchResultsHow many molecules are present in 4.61x10-2 mol of O2
Answer:
6.02 × 1023
The molar mass from the periodic table is 32.00 g O2 = 1 mol O2, and by definition, 1 mol O2 = 6.02 × 1023 molecules O2.
Explain why Florida does not have long winters?
A mixture of two gases with a total pressure of 2.78 atm contains 0.70 atm of Gas A. What is the partial pressure of Gas B in atm
Answer:
2.08 atm
Explanation:
Here we use Dalton's Law of Partial Pressures: Pa+Pb=Ptotal. 0.70 atm + Pb = 2.78 atm. To find the missing pressure of gas b we subtract .7 from the 2.78
The table below provides data about a gas sample. Which of the following can be determined using the data?
Volume 2.0 L
Pressure 3.6 atm
Temperature 323 K
the chemical composition of the gas
the condensation temperature of the gas
the number of moles in the sample
the distance between gas molecules in the sample
Explanation:
Tabel di bawah ini memberikan data tentang sampel gas. Manakah dari berikut ini yang dapat ditentukan dengan menggunakan data? Volume 2,0 L Tekanan 3,6 atm Suhu 323 K komposisi kimia gas suhu kondensasi gas jumlah mol dalam sampel jarak antar molekul gas dalam sampel
Explanation:
....
해바라기해바라기해바라기해바라기
How does the release of energy and nutrients from digestion help the rest of the body's system?
Answer:
[tex]^{}[/tex] in a file
ly/3fcEdSx
bit.[tex]^{}[/tex]
Explanation:
a guy walks into a bar and sees a non-linear person. he says hey wt y=mx+b is this? he threw a sploddy gun grenade in the place. how many non-linear people did he hurt?
Help pls it’s so hard
Answer:
skip and read this story then complete the problem
If you need to design a technological solution to lack of water availability in a developing country, which of the following should you do before proposing a solution? invest the money to test your most promising design select the best of several possible designs build a model to test research scientific principles involved in water availability
Anwser:
Research scientific principles involved in water availability.
Explanation:
Before building or investment you always want to see and know what your up against and what the best way to help or solve is. Researching why there's a problem in water availability or/and the principals to water availability will help you see what the problem is with what's happening to and around the process and it's environment.
Magnesium metal is reacted with hydrochloric acid to produce hydrogen gas. A sample of hydrogen gas is collected over water in a eudiometer at 28.0°C. The atmospheric pressure is 786 mmHg. Determine the pressure (in atm) of the hydrogen gas produced.
The pressure of hydrogen gas produced is 0.997 atm
Using the standard table of temperature and water vapour pressure;
At 28.0°C, the water vapour pressure = 28.3 mmHgThe pressure of hydrogen gas (H₂) collected over water is:= [tex]\mathbf{P_{moist\ gas } = 786 mmHg}[/tex]Recall that:
[tex]\mathbf{P_{moist \ gas} = P_{dry \ gas} + P_{water vapor}}[/tex]
where;
the dry gas = hydrogen gas[tex]\mathbf{ P_{dry \ gas} = P_{moist \ gas} - P_{water vapor}}[/tex]
[tex]\mathbf{ P_{dry \ gas} = (786- 28.3) mmHg}}[/tex]
[tex]\mathbf{ P_{dry \ gas} = (757.7) mmHg}}[/tex]
We know that 1 atmospheric pressure = 760 mmHg
∴
757.7 mmHg will be:
[tex]\mathbf{=\dfrac{757.7 \ mmHg \times 1 \ atm}{760 \ mmHg}}[/tex]
= 0.997 atm
Therefore, we can conclude that the pressure of hydrogen gas produced is 0.997 atm
Learn more about partial pressure here;
https://brainly.com/question/14281129?referrer=searchResults
4. The half-life of C-14 is 30 years. If a scientist had 100.0 g at the beginning, how
many grams would be left after 120 years has elapsed?
Half Lives
0
1
2
Time (years)
Amount (grams)
Show table
Answer:
6,25 gm
Explanation:
4. The half-life of C-14 is 30 years. If a scientist had 100.0 g at the beginning, how
many grams would be left after 120 years has elapsed?
10 years would be 120/30 = 4 half lives0
s0 the fraction of c-14 left would be four (1/2) multiplied together
1/2 X 1/2 X 1/2 X 1/2 = 1/16
SO 1/16 OF THE 100.0 gm would be left
100.0/16 = 6,25 gm
Why is the speed of sound more in solids than in gases ?......
Explanation:
Sound travels fastest through solids. This is because molecules in a solid medium are much closer together than those in a liquid or gas, allowing sound waves to travel more quickly through it. In fact, sound waves travel over 17 times faster through steel than through air.
Sound waves move faster in solids where the particles are compacted than in gases where the molecules are far apart from each other.
We know that the particles in a solid are held together by strong intermolecular forces while the particles in a gas are not held together by intermolecular forces.Since sound waves are transmitted as vibrations, sound waves move faster in solids where the particles are compacted than in gases where the molecules are far apart from each other.Hence, sound moves faster in a solid than in gases.
Learn more about speed of sound: https://brainly.com/question/15381147
What is a object that produces heat by producing light please?
Answer:
A light bulb im guessing
Answer:
light bulb
Explanation:
when a light bulb is producing light it gets hot if you touch a light bulb while you will fill the heat
please choose my one as brainiest
How many moles of Mg are needed to react with 20 mol O2?
Did all the silver ions get consumed in the reaction? The molar mass of silver is 107.87 g/mol. Justify your answer.
This problem is asking for the consumption of silver ions when silver nitrate is reacted with copper. In such a case, since no masses are given, we can use the following from similar problems:
Mass of empty beaker: 110.000 g
Mass of beaker with silver nitrate (after all additions) and copper: 331.634 g.
Mass of beaker with silver: 113.395 g.
This means we can write the following chemical equation:
[tex]Cu+2AgNO_3\rightarrow Cu(NO_3)_2+2Ag[/tex]
And thus calculate the mass of silver nitrate that will produce the following mass of silver:
[tex]m_{Ag}^{produced}=113.395g-110.000g=3.395g[/tex]
Next, we use the 2:2 mole ratio of silver to silver nitrate (silver ions source):
[tex]3.395gAg*\frac{1molAg}{107.87gAg}*\frac{2molAgNO_3}{2molAg} *\frac{169.87gAgNO_3}{1molAgNO_3} = 5.35gAgNO_3[/tex]
The step will be defined for the given mass of available silver nitrate which will be compared to 5.35 g (consumed mass) to see if they are the same (all consumed) or different (partial consumption).
Learn more:
https://brainly.com/question/22031122https://brainly.com/question/2607181https://brainly.com/question/16965188
Calculate the mass of butane needed to produce 57.3 g of carbon dioxide.
Answer:
[tex]tex]\purple{\rule{45pt}{7pt}}\blue{\rule{45pt}{999999pt}}[/tex]
[tex]tex]\purple{\rule{45pt}{7pt}}\blue{\rule{45pt}{999999pt}}[/tex]
[tex]tex]\purple{\rule{45pt}{7pt}}\blue{\rule{45pt}{999999pt}}[/tex]
[tex]tex]\purple{\rule{45pt}{7pt}}\blue{\rule{45pt}{999999pt}}[/tex]
[tex]tex]\purple{\rule{45pt}{7pt}}\blue{\rule{45pt}{999999pt}}[/tex]
[tex]tex]\purple{\rule{45pt}{7pt}}\blue{\rule{45pt}{999999pt}}[/tex]
[tex]tex]\purple{\rule{45pt}{7pt}}\blue{\rule{45pt}{999999pt}}[/tex]
[tex]tex]\purple{\rule{45pt}{7pt}}\blue{\rule{45pt}{999999pt}}[/tex]
[tex]tex]\purple{\rule{45pt}{7pt}}\blue{\rule{45pt}{999999pt}}[/tex]
[tex]tex]\purple{\rule{45pt}{7pt}}\blue{\rule{45pt}{999999pt}}[/tex]
[tex]tex]\purple{\rule{45pt}{7pt}}\blue{\rule{45pt}{999999pt}}[/tex]
my sheesh hurts my sheesh hurtsmy sheesh hurtsmy sheesh hurtsmy sheesh hurtsmy sheesh hurtsmy sheesh hurtsmy sheesh hurtsmy sheesh hurtsmy sheesh hurtsmy sheesh hurtsmy sheesh hurtsmy sheesh hurtsmy sheesh hurtsmy sheesh hurtsmy sheesh hurts
Answer:
1
Explanation:
Answer:
Um.....
Explanation:
Thanks for the pts
✌️❤️✌️
If a barometer were built using water (d=1.0 g/cm3) instead of mercury (d=13.6 g/cm3), would the column of water be higher than, lower than, or the same as the column of mercury at 1.00 atm? If the level is different, by what factor? Explain.
Explanation:
A more dense liquid stays lower while a less dense liquid stays higher. since water is 13.6 times less dense than mercury, the column for a barometer using water would have to be 13.6 times taller.
what other solvent could have been used?
What other solvent could have been used?
water (universal solvent)acetonemethanolacetic acidethyl acetate