Burning a sugar cube is a chemical change. Fire activates a chemical reaction between sugar and oxygen. The oxygen in the air reacts with the sugar and the chemical bonds are broken. Burning sugar leads to reaction of sugar with oxygen in air and leads to formation of carbon dioxide and water. The change is irreversible and is thus a chemical change
Although tom was a poor student, he studied very well
Explain which intermolecular force is primarily responsible for the unusually high boiling point of H2OH2O. Compare the strengths of intermolecular forces of attraction present in a sample of liquid water to the strengths of intermolecular forces of attraction present in liquid samples of H2SH2S, H2SeH2Se, and H2TeH2Te. Justify your answer using the information presented in both tables, and complete the statements below.
Answer:
See explanation
Explanation:
Intermolecular forces are forces of attraction that exist between molecules of a substance in a particular state of matter.
The dominant intermolecular force of attraction in H2O is the hydrogen bond. The hydrogen bond exists between molecules of a substance when the substance is made of hydrogen atoms bonded to atoms of a highly electronegative element. Hence, strong hydrogen bonding accounts for the high boiling point of water.
The magnitude of hydrogen bonding between molecules depends on the electro negativity of the atoms to which hydrogen is bonded.
The more the electro negativity of the atoms to which hydrogen is bonded, the greater the magnitude of intermolecular hydrogen bonding.
Since the electro negativity of elements decrease down the group, the strength of intermolecular hydrogen bonding between the molecules decreases as follows;
H2O> H2S> H2Se> H2Te
How does knowing the reactants and
help you classify a chemical reaction?
if you know what kind of chemical a reactant is, it can help you to quickly distinguish the chemical reaction.
Ex:
HCl + KOH <---> KCl + H2O
We can look at the reactants and identify that this reaction is an acid-base reaction because HCl is an acid (it gave a proton) and KOH is a base (it accepted the proton)
Answer:
Products
Explanation:
I just got it right.
My theoretical yield is 14 grams of water. I actually produced 6 grams of water. What is my percent yield?
Answer:
Pertaining to the interrogate, the answer to such is acknowledged and henceforth disseminated as 43.0%
Explanation:
To evaluate such, the following must be comprehended:
Percent Yield Calculator:
% Yield = (What You Actually Got / What You Should Theoretically Get) * 100
The following variables may be denoted, as stated within the interrogate:
Yielded/Produced: 6 grams.
Theoretical Yield: 14 grams.
(6 g/14 g) * 100 = 42.8571428571
*Grams measurement cancels*
42.8 ==> 43.0%
Thus, if rounded to the nearest tenth, the percent yield is equivalent to 43.0%.
calculate molarity, molality and mole fraction of 28 percent aqueous solution of a solute with molar mass 11.5 g per mole and density is 1.25 g per mole
Explanation:
Aight, I'mma give tell ya an easy way for this question. look at this Forumla
M=
[tex] \frac{10ad}{m} [/tex]
a explains the percentage of aqueous solution
d is the density
m is the molar mass
right, let's just hop to it
M=10×28×1.25/11.5====> M=30.43
Suggest why a young baby needs a lot of calcium
9. a) Name salt that can be prepared by precipitation
I think its the substances that sublimes
Fe + HNO₃ -> Fe(NO₃)2 + H₂
Vitamin C is a water-soluble vitamin, so your body doesn't store it. You have to get the required amount from your diet (citrus fruits are a great source!), or you could take a daily vitamin C supplement pill. Vitamin C is ascorbic acid, so to determine how much vitamin C (acid) has been placed in each pill, you could do an acid-base titration. One vitamin C pill was dissolved in water and titrated to an endpoint by 16.00 mL of a 0.447 M solution of NaOH. How many grams of ascorbic acid were there in the pill? (MW of ascorbic acid is 176.1 /mol). Explain and show your work.
Answer:
Mass of ascorbic acid in the pill = 7.152 x 176.1/1000 = 1.26 g
Explanation:
The mass of ascorbic acid in the pill would be,
1.26 g
Now,
Moles of ascorbic acid = Moles of NaOH = 0.447 M x 16 ml = 7.152 mmol
Mass of ascorbic acid in the pill = 7.152 x 176.1/1000 = 1.26 g
Question 3: Functional Groups
Identify the type of molecule from the name of the molecule.
Answer:
1. Organic Alcohol
2. Ester (specifically acetate ester)
3. Organic Alcohol
4. Carboxylic acid
5. Ketone
6. Ether
7. Amine
Explanation:
You can tell what type it is both from the nomenclature and looking at the functional group on the molecular structure. Hope this helps!
Mother is frying fish in the kitchen. The aroma of fried fish can be smelled by Sofea who is sitting in the living room. Explain how the aroma of the fried fish reach the living room.
Answer:
through process of diffusion
Explanation:
air particles and odours move freely in all directions and eventually spreads out thus reaching the sitting room
The process of diffusion causes the particles of the aroma of the fried fish to reach the living room.
What is diffusion?Diffusion can be described as the net movement of anything such as molcules, or energy from a region of higher concentration to a region of lower concentration. Diffusion is generally driven by a gradient in Gibbs free energy or chemical potential.
The concept of diffusion can be used in fields such as physics, chemistry, biology, sociology, economics, and finance. The central idea of diffusion is common that a substance undergoing diffusion spreads out from a point or location at which there is a higher concentration of that substance.
A gradient can be defined as the change in the value of an amount such as concentration, pressure, or temperature with a change in another variable, distance.
A change in concentration over a distance is known as a concentration gradient, and a change in pressure over a distance is known as a pressure gradient.
The Latin word diffusion means "to spread out." Therefore, the aroma of the fried fish diffuses and reaches to lining room.
Learn more about diffusion, here:
https://brainly.com/question/14852229
#SPJ2
Calculate the amount of solute excess out when the 60 gm of saturated solution of
NH4Cl having solubility of 57 at 60 ℃ is cooled to 20 ℃ , the solubility being 35.
Answer:
weight of salt = 90 gram,
solubility = 50
sing formula
solubility of solute =
weightofsolventinsaturatedsolution
weightofsoluteinsaturatedsolution
×100
or 50=
weightofsolventinsaturatedsolutio
90gm
×100
so weight of solvent in saturated solution =
50
90gm
×100=180gm
Hence 180 gm of water is required to prepare a saturated solution.
Name three metals on the periodic table and their uses
PLS HELP
why atoms of magnet differ from normal atoms?
Answer:
ones in magnets r close together while others can be spread apart
PLZ HELP ME WITH MY WORK
What is a compound?
A substance that is made from two different metals
B. A substance that cannot be broken into simpler substances
C. A substance that is made using a chemical reaction
D. A substance that can be separated by physical means
Answer:
C.
Explanation:
Answer A is incorrect because a compound doesn't have to be made with only metals.
Answer B is incorrect because that is actually the definition of a pure element.
Answer C is correct because to make a compound, there has to be a chemical reaction where bonds are formed and an entirely new substance is created.
Answer D is incorrect because compounds cannot be separated by physical means.
Hope this helps :D
A block of dry ice (-40°C) is placed in contact with an ice cube (-10°C).
What will happen, assuming no chemical reactions occur?
O Heat will flow from the ice cube to the dry ice.
O Heat will flow from the dry ice to the ice cube.
O There is no way to tell without a thermometer
O No heat will flow.
Explanation:
Answer is that : no heat will flow
Answer:
Heat will flow from the ice cube to the dry ice
Explanation:
Xà phòng hoá hoàn toàn 22,2g hỗn hợp gồm 2 este HCOOC2h5 và ch3cooch3 bằng dung dịch naoh 1m ( đun nóng) thể tích dung dịch naoh tối thiểu cần dùng là
Answer:
I can't understand your language? can you write in English
I'm sorry
The addition of solute particles into a solution causes:
A. the solvent particles to be attracted to the solute particles and to have less kinetic energy.
B. the solute particles to bump the solvent particles out of the solution, making it easier to boil.
C. the solute particles to form seed crystals and make the solution freeze more easily.
D. the solvent particles to be spread further out and have more to move, increasing their kinetic energy.
Answer:
D. the solvent particles to be spread further out and have more to move, increasing their kinetic energy.
Explanation:
The addition of solute particles results in an increased boiling point. As the solutes increases so does the energy inside as the solutes add and occupies more space near the surface of the liquid.According to the kinetic molecular theory, what happens to a liquid when it is transferred from one container to another?
ОООО
O The volume and the shape stay the same.
The volume increases to fill the new container, but the shape stays the same.
The volume stays the same, but the shape changes to fit the new container.
The volume and the shape change to fill the new container.
Answer:
C. The volume stays the same, but the shape changes to fit the new container.
Explanation:
It changes shape to fit the container since it's a liquid.
How many molecules are in 35.5 grams of carbon dioxide?
Answer:
you have to use the avogadro's constant of 6.023×10^23 to calculate the number of molecules of carbon dioxide.and you also have to use the molecular mass which is 44.
35.5/44×6.023×10^23
=4.85×10^23
I hope this helps and sorry if it's wrong
I need help getting this done
Answer:
I put the right structures in the pictures for you
What is the energy of a photon emitted with a wavelength of 448 nm?
O A. 2.97 x 10-22 J
O B. 4.44 x 10-19 J
O C. 8.91 x
10-23 J
O D. 1.48 x 10-27 J
Answer: B is the correct answer
Explanation:
The energy of a photon is 4.44×[tex]10^{-19}[/tex]J for the wavelength of 448 nm.
So, option (B) is correct. This can be calculated by using the energy formula.
The energy of a photon:The energy of a photon is said to be photon energy. It is directly proportional to the photon's electromagnetic frequency and inversely proportional to the wavelength. If the frequency of the photon is high then its energy is also high.
The energy of a photon, E=hc/λ
Given data:Given that,
λ = 448nm
h= 6.63×[tex]10^{-34}[/tex]J/s
Calculating the energy:E = 6.63×[tex]10^{-34}[/tex]×3×[tex]10^8[/tex]/448×[tex]10^-^9[/tex]
E = 4.44×[tex]10^{-19}[/tex] J
Hence option (B) is correct.
Therefore, the energy of a photon emitted with a wavelength of 448nm is 4.44×[tex]10^{-19}[/tex] J.
Learn more about the energy of photons here:
https://brainly.com/question/7957705
#SPJ2
PLZ HELP ME WITH MY WORK
Answer:
c. H2 andO2
I think this is the answer not sure ok
Formation of HCl from H₂and Cl₂ is example of
photochemical
electrochemical
displacement
Answer:
Combination reaction.
Explanation:
The reaction depicted in the question is;
H2 (g) + Cl2 (g) ⟶ 2HCl (l)
Now, this reaction shows that two reactants namely hydrogen and chlorine react to form a single product named Hydrogen chloride. This process is called combination reaction.
What is the mass percent of a sodium fluoride solution prepared by dissolving 0.64 moles of sodium fluoride into 63.5 grams of water?
The mass percent of a sodium fluoride solution prepared by dissolving 0.64 moles of sodium fluoride into 63.5 grams of water is 29.7%.
What is mass percent ?Mass percent is a means to describe a component in a specific combination or to convey a concentration. The mass percentage used to describe the solution composition indicates the mass of solute contained in a given mass of solution.
To determine the mass percent of an element in a compound, we divide the mass of the element in one mole of the compound by the compound's molar mass and multiply the result by 100.
Given:
Number of moles = 0.64 moles
Moles of sodium fluoride = Given mass/molar mass
0.64 moles = Mass / 42
Mass = 26.88gram
Mass % = Mass of solute/ mass of solution × 100
= 26.88/90.48 × 100
= 29.7 %
Thus, 29.7 % is the mass percent of a sodium fluoride solution prepared by dissolving 0.64 moles of sodium fluoride into 63.5 grams of water
To learn more about the mass percent, follow the link;
https://brainly.com/question/5394922
#SPJ6
Currently, nuclear energy provides only a small fraction (~10%) of energy used in the United States. In some other places, like France, it is close to 80%. Do you think nuclear energy will ever be a more widely used source of energy in the United States? Why or why not?
PLEASE HELP ASAP PLEASEEE
Nuclear energy is currently within almost every country becoming a growing source of energy use since it can provide a lot of energy within a short amount of time with little resources used to create it. It is quite possible that within the next few generations that nuclear energy could become a much larger source of energy within the United States. Although, many countries after the leak have resorted to other means of energy sources learning from the mistakes of Japan.
Hope this helps :)
Mercury poisoning is a debilitating disease that is often fatal. In the human body, mercury reacts with essential enzymes leading to irreversible inactivity of these enzymes. If the amount of mercury in a polluted lake is 0.4 Hg/mL, what is the total mass in kilograms of mercury in the lake
Answer:
The total mass of mercury in the lake is 631,542.7 kg
Explanation:
Question: The given dimensions of the lake as obtained from a similar question posted online are;
The surface area of the lake, A = 100 mi²
The lake's average depth, d = 20 ft.
The concentration of the mercury, C = 0.4 μg Hg/mL = 0.4 × 10⁻⁶ kg Hg/L
Therefore, we have;
The volume of water mixture in the lake, V = A × d
∴ V = 100 mi² × 20 ft. = 2,787,840,000 ft.² × 20 ft. = 55,756,800,000 ft.³
1 ft³ = 28.31685 L
∴ 55,756,800,000 ft.³ = 55,756,800,000 ft.³ × 28.31685 L/ft.³ = 1.57885675 × 10¹² L
The total mass of mercury in the lake, m = C × V
∴ m = 0.4 × 10⁻⁶ kg Hg/L × 1.57885675 × 10¹² L = 631,542.7 kg
The total mass of mercury in the lake, m = 631,542.7 kg.
balance the equation:2Na+3H2O-2NaOH+H2
Answer:
2Na + 2H2O → 2NaOH + H2
Explanation:
A balanced equation is an equation for a chemical reaction in which the number of atoms for each element in the reaction and the total charge are the same for both the reactants and the products.
Realiza los cálculos para determinar la cantidad de KOH 90%, que se necesita para preparar 100 ml de solución 1N.
Answer:
6.23 KOH 90% son necesarios
Explanation:
Una solución 1N de KOH requiere 1equivalente (En KOH, 1eq = 1mol) por cada litro de solución.
Para responder esta pregunta se requiere hallar los equivalentes = Moles de KOH para preparar 100mL = 0.100L de una solución 1N. Haciendo uso de la masa molar de KOH y del porcentaje de pureza del KOH se pueden calcular los gramos requeridos para preparar la solución así:
Equivalentes KOH:
0.100L * (1eq / L) = 0.100eq = 0.100moles
Gramos KOH -Masa molar: 56.1056g/mol-:
0.100moles * (56.1056g/mol) = 5.61 KOH se requieren
KOH 90%:
5.61g KOH * (100g KOH 90% / 90g KOH) =
6.23 KOH 90% son necesarios2.
In photosynthesis, which substances are used up, which are produced and which are necessary
but remain unchanged after the reaction?
used up
produced
remain
A
carbon dioxide
water
oxygen
A
8
chlorophylt
carbon dioxide
water
с
oxygen
starch
cellulose
D
water
oxygen
chlorophyll
D. Water is used up, Oxygen is produced and Chlorophyll is necessary, but remains unchanged.
