which of the following is a physical change? 1.burning paper 2.grinding wheat 3.electrolysis of water 4.cooking rice​

Answers

Answer 1

Answer:

2 grinding of wheat is just a physical change

plz brainlist


Related Questions

How does kinetic energy transform into potential energy?

Answers

kinetic energy is converted to potential energy because while it is not actually doing work, it has the potential to do work. If we drop the object from the shelf or release the spring, that potential energy is converted back into kinetic energy.

TIMED HELP ASAP

19.11 g of MgSO₄ is placed into 100.0 mL of water. The water's temperature increases by 6.70°C. Calculate ∆H, in kJ/mol, for the dissolution of MgSO₄. (The specific heat of water is 4.184 J/g・°C and the density of the water is 1.00 g/mL). You can assume that the specific heat of the solution is the same as that of water.

Answers

Answer:

TIMED HELP ASAP

19.11 g of MgSO₄ is placed into 100.0 mL of water. The water's temperature increases by 6.70°C. Calculate ∆H, in kJ/mol, for the dissolution of MgSO₄. (The specific heat of water is 4.184 J/g・°C and the density of the water is 1.00 g/mL). You can assume that the specific heat of the solution is the same as that of water.

Answer:

-21.03 kJ/mol

Explanation:

∆H is enthalpy. Enthalpy is the total heat content of a system.

So we can establish that ∆H = q (heat)

The formula for heat (q)

q = cm∆T

c = specific heat capacity

m = mass of substance

∆T= change of temperature

Since we are calculating the enthalpy of the SOLUTION. We must account for both the mass of water and the mass of MgSO₄ in our q formula.

All you gotta do is plug and chug at this stage.

∆H = q     = cm∆T = (4.184)(19.11+100.0)(6.70) = 3338.986808 Joules

We have now calculated the heat (aka enthalpy) of the solution.

BUT

Remember! The problem asked for enthalpy in kj....

Use this conversion factor.

1000 J = 1 kJ

3338.986808 Joules * 1kJ/1000 J = 3.338986808 kJ

We were asked to find ∆H for the dissolution of MgSO4  in units of kj/mol so we are not finished.

Take the grams of MgSO4 in the problem  and convert it into moles using its molar mass.

MgSO4 molar mass = 120.3676 g

1 mol = 120.3676 g MgSO4   <---- Use this as a conversion factor

19.11 g MgSO4 * 1 mol MgSO4/120.3676 g = 0.15876365 mol MgSO4

Now that you've calculated the moles of MgSO4 in this solution. You can divide your heat by it.

q dissolution = 3.338.986808 kJ/ 0.15876365 mol =  21.03 kj/mol

Note that the problem tells us that the temperature of water increases.

This means that the water is experiencing an endothermic process (heat is being absorbed from MgSO4) . Mathematically, this would be indicated by a positive sign. ---> +q

We can assume MgSO4 is losing heat as it is placed into the water. It is experiencing an exothermic process (heat is being lost).  Mathematically, this would be indicated by a negative sign. ----> -q

So if we're calculating the enthalpy for the dissolution of MgSO₄ ....the value we've arrived at must be negative.

Answer

∆H = 21.03 kj/mol :)))))

I hope that helped...I feel like my explanation was a bit convoluted.

If 30.0 grams of AlC3 is produced in the reaction, how many grams of HCI must have reacted?

Answers

Answer:

Al2O3 + 6HCl ==> 2AlCl3 + 3H2O ... balanced equation

moles Al2O3 present = 30.0 g x 1 mol/101.96 g = 0.294 moles

moles HCl present = 30 g HCl x 1 mol/36.5 g = 0.822 moles HCl

HCl is LIMITING as it takes 6 moles HCl for each 1 mol Al2O3 and here that is not enough. It will run out first.

Now, using the limiting reactant, we find the moles and mass of AlCl3 that can be formed.

0.822 moles HCl x 2 moles AlCl3/6 moles HCl = 0.274 moles AlCl3 formed

mass of AlCl3 = 0.274 moles AlCl3 x 133 g/mole = 36.4 g AlCl3 formed

Name each compound. Do not capitalize element names. An example can be seen
below.
Ex. SF6: sulfur hexfluoride
a. H2O:
b. PC15:
C. SiF4:
d. N20

Answers

Answer:

a. H2O: dihydrogen monoxide

b. PCl5: Phosphorus pentachloride

c. SiF4: Silicon tetrafluoride

d. N20: dinitrogen oxide

what is transition state​

Answers

Answer:

transition state is a point in which electrons been removed from the atom

Answer:

The highest energy structure in the reaction coordinate.

Explanation:

How are the vapor pressure and boiling point of alkynes affected as the chain length increases?

Answers

Answer:

Answer to the following question is as follows;

Explanation:

Alkynes' vapour pressure and normal boiling points are altered when chain length grows, since vapour pressure rises while boiling point falls.

Vapour pressure always include pressure entered by vapour with its condensed phase, pressure include molecules force of attraction include vapour

PLZ HELP According to the atomic model Which particles are found In the same part of the atom
a. protons electrons neutrons
B.protons and neutrons
C.protons and ​electrons
D.electrons and neutrons​

Answers

protons and neutrons
B I think its the best answer
Hope its help for your questions

what are the intermolecular forces of Sulfate ion

Answers

Answer:

oh it's easy

Explanation:

Take the hydrate

N

a

2

S

2

O

3

5

H

2

O

. Are there ionic forces between the

N

a

+

and the

S

2

O

2

3

and ion-dipole forces between the cation/anions and the water?

What is the total pressure in millimeters of mercury,
exerted by the gas mixture

P= _______ units?

Answers

Answer:

87059.50558 pa

Explanation:

Dalton's law of partial pressure states that Ptotal=P1 +P2+ P3

417mmHg + 150mmHg +86mmHg =653 mmHg

convert it to Pa, your answer is 87059.50558Pa.

I hope I'm of help to you

is SrO a conductor of electricity

Answers

Answer:

No and Yes

Explanation:

it depends bc its an ionic compound, therefore can't conduct electricity when SOLID, BUT unless it DISSOLVES in water it can conduct

Indicar que elemento es de transición *

a) Calcio

b) Radio

c) Hierro

d) Carbono

e) Azufre

Sabiendo que las configuraciones electrónicas son correctas, determinar qué analogía es incorrecta *

a) 47Ag: [Kr] 5s2 4d9  I – B
b) 27Co: [Ar] 4s2 3d7  VIII – B
c) 41Nb: [Kr] 5s2 4d3  V – A
d) 50Sn: [Kr] 5s2 4d10 5p2  IV – A
e) N.A.

porfaaaaaaaaaaaaaaaaaaaa

Answers

Answer:

c hierro

no se la otra sorry

Which element has 2 valence electrons in the 2s sublevel?

Answers

Answer:

beryllium is the answer.

I hope this will help you

copper II carbonate in a crucible produced only 7g of copper II oxide. What was the percentage yield of copper II oxide​

Answers

The question is incomplete, the complete question is;

.On heating 12.4 g of copper (II) carbonate in a crucible only 7.0g of copper (II) oxide was produced. What was the % yield of copper (II) oxide ? [Cu=64,C=12,O=16]

Answer:

87.5%

Explanation:

CuCO3 -------> CuO + CO2

Number of moles of CuCO3 = 12.4g/123.55 g/mol = 0.1 moles

Since the reaction is 1:1,

Mass of CuO produced = 0.1 moles × 80g/mol = 8 g

Hence,

% yield = actual yield/theoretical yield × 100

% yield = 7/8 × 100

% yield = 87.5%

Anyone please help I’m in summer school please

Answers

Answer:

1. Absolute time, also known as Newtonian time is a time that exists independent of the observer of the time, and therefore, can only be expressed through mathematics

Absolute dating is a dating method that makes use of the radioactive property of matter and is determined through dating of radioactive isotopes present

Absolute time (dating) is found through radioactive dating

2. Radioactive isotopes are atoms that have the property of unstable proton neutron combination or excess energy nucleus. They can be fined as unstable element

3. A stabilized isotope are the decay product atoms of the element which are non radioactive.

4. The half life is the time it takes the original isotope to decay into the decay product

5. To determine the age of a rock, the proportion of the original isotope to the amount of decay product in the rock is compared

6. The isotope used to date organic materials is carbon-14

7. The isotope used to date rocks with comparable age to the Earth is Uranium-238 that has a half life of 4.468 billion years

8. The half life of carbon-14 is only 5,700 years while the age of a dinosaur is between 245 and 66 million years ago, and therefore, carbon is absent in most fossils

9. Uranium-238 is only found in igneous or volcanic rocks and not in metamorphic rocks, therefore, fossils  of dinosaur as well as other fossils that are buried in sedimentary materials, including sand and clay, cannot be determined by Uranium-238

Explanation:

Calculate the molar mass AND identify the gas if 3.25 kg of this gas is stored in a 15.00 L tank and exerts a pressure of 120.0 atm at a constant temperature of 66.0°C.

Answers

Answer:

is your question correct

.

..

.

.

.

or not

How many grams of hydrogen is produced from 12.5 G of MG reacting with hydrochloric acid in this balanced equation?
Mg+ 2HCL —>MgCl2+H2

Answers

Answer:

1.03 grams of hydrogen is produced from 12.5 g of Mg reacting with hydrochloric acid.

Explanation:

The balanced reaction is:

Mg+ 2 HCl → MgCl₂ + H₂

By stoichiometry of the reaction, the following amounts of moles of each compound participate in the reaction:

Mg: 1 moleHCl: 2 molesMgCl₂: 1 moleH₂: 1 mole

Being the molar mass of each compound:

Mg: 24.31 g/moleHCl: 36.45 g/moleMgCl₂: 95.21 g/moleH₂: 2 g/mole

By reaction stoichiometry, the following mass amounts of each compound participate in the reaction:

Mg: 1 mole* 24.31 g/mole= 24.31 gHCl: 2 moles* 36.45 g/mole= 72.9 gMgCl₂: 1 mole* 95.21 g/mole= 95.21 gH₂: 1 mole* 2 g/mole= 2 g

Then you can apply the following rule of three: if by stoichiometry 24.31 grams of Mg produces 2 grams of H₂, 12.5 grams of Mg produces how much mass of H₂?

[tex]mass of H_{2} =\frac{12.5 grams of Mg* 2 grams of H_{2}}{24.31 grams of Mg}[/tex]

mass of H₂= 1.03 grams

1.03 grams of hydrogen is produced from 12.5 g of Mg reacting with hydrochloric acid.

draw the structure of iso -pentylpropanoate​

Answers

i dont know how to draw bu tjisy drow stick people sjdiwkicksickenf

Is FeS iron (ll) sulfide or iron (lll) sulfide?

Answers

Answer:

the valence of S is -2. For FeS to be neutral the valence of Fe used must be +2

and since Iron (II) has its valency 2, FeS will be Iron (II) Sulfide.

how much energy is required to melt 2kg of aluminium

Answers

800kj----------




800kj----------

What is pH value in simple words?

Answers

The pH value is a measure of how acidic/basic a substance is.

The range goes from 0 to 14, with 7 being neutral.

pH values that are less than 7 indicate acid (acidity), whereas a pH value greater than 7 indicates a base (basic).

pH is really a measure of the relative amount of free hydrogen and hydroxyl ions in the substance.

What does this chemical energy reaction describe? Water-hydrogen+oxygen

Answers

Answer:

may be you mean water= hydrogen + oxygen, this reaction describes that water is made by the combination of hydrogen and oxygen.

water is made by the chemical reaction of hydrogen and oxygen

option with explaination

Answers

Answer:

B. it's water of crystallization.

the water of crystallization, that is the number of molecules of water attached to One Copper atom gives blue color to the hydrated salt (CuSO4.5H2O)

Question 1: Alkanes, Alkenes, and Alkynes

Complete the table by labeling each molecule an alkane, alkene, or alkyne.

Answers

Answer: The labelling of each molecule is listed below:

B.) alkyne

C.) Alkane

D.) alkyne

I.) alkene

Explanation:

In organic chemistry, if an organic compound contains atoms joined only by single covalent bonds, the compound is said to be saturated. The ALKANES are said to be saturated hydrocarbons. For example butane and hexane that is shown in option F and G respectively. If an organic compound contains carbon atoms joined by double or triple covalent bonds, the compound is said to be unsaturated. For example Octene and butyne as seen in option E and H respectively.

Furthermore, hydrocarbons possess8g a set of carbon-carbon double covalent bonds,>C=C<, in their carbon chains form the homologous series called ALKENES while those possessing a set of carbon-carbon triple covalent bond in their carbon chains form the ALKYNE series

From the questions above, a more informative formula known as the structural formula is used to represent the various organic substances. The formula indicates how the atoms are arranged within the molecule of a substance. A structural formula is usually shown as a planar for convenience and does not imply a flat molecule. It shows the actual arrangement of the atoms in space and the angles between the bonds. Therefore options C, D and I are alkane,alkyne and alkene respectively.

Explain the charge, the location and the size of protons, and electron.

Answers

Protons are positively charged particles that are located inside the nucleus at the center of the atom. Protons have a mass of 1 amu or atomic mass unit.

Electrons are negatively charged particles found outside the nucleus. Electrons have a mass of approximately 0 amu or atomic mass unit.

hope it helps :)

please mark brainliest!!!

Please help!!
Chemical reactions and Nuclear reactions cause matter to change in different ways. Witch TWO statements decribe how matter changes only in nuclear reactions.
• A. The automic nuclei change.
• B. Some energy is transformed into mass.
• C. The total mass of the reactions is conserved.
• D. New elements are formed​

Answers

Answer:

Answer is 2nd

Explanation:

some energy is transformed into mass

An organic compound has the empirical formula C2H4O. what is the compound?

a. butanoic acid
b. butanol
c. ethanoic acid
d. ethanol

Answers

Answer:

The correct answer is - butanoic acid

Explanation:

An empirical formula is the general formula or base formula that is the simplest positive integer ratio of atoms present in a compound. The empirical formula is specific to specific compounds or types of compounds.

Among the given options, the empirical formula C2H4O is butanoic acid as the molecular formula of butanoic acid is - C4H8O2 which is multiple of C2H4O. Other compounds have different than this empirical formula.

name and describe four different types of chemical reactions and explain how you can predict which type might occur

Answers

Answer:

1. Combination (Synthesis) reaction

A + B → AB

2. Decomposition reaction

AB → A + B

3. Displacement reaction

A + BC → AB + C

4. Double displacement reaction

AB + CD → AD + BC

5. Combustion reaction

[tex]CH_{4} + 20_{2} → CO_{2} 2Hx_{2} O[/tex]

A combination reaction, also known as a synthesis reaction, is a reaction in which two or more substances combine to form a single new substance. Combination reactions can also be called synthesis reactions.

A decomposition reaction is a reaction in which a compound breaks down into two or more simpler substances.

A single-replacement reaction is a reaction in which one element replaces a similar element in a compound.

A double-replacement reaction is a reaction in which the positive and negative ions of two ionic compounds exchange places to form two new compounds.

A combustion reaction is a reaction in which a substance reacts with oxygen gas, releasing energy in the form of light and heat. Combustion reactions must involve  O2 as one reactant. The combustion of hydrogen gas produces water vapor

Explanation: Hope this helps and good luck :))

Plz Help I have One more time To retake and I can't fail it..​

Answers

Answer:

D. is the answer which is copper is a conductor because it's valency can move from atom to atom.

¿Qué relación tienen los microorganismos patógenos con el cov1d
19 ?

Answers

Answer:

Lumayan poin gratis...

gw gatau lu pake bahasa apaan njink

On the set of a movie, dry ice (solid carbon dioxide) is used to make the appearance of fog. After the dry ice is taken out of cold storage, it is placed on the ground. As dry ice warms, it converts from a solid directly to a gas. Gaseous carbon dioxide has a density greater than air, thus allowing it to move across the ground as if it were fog. Which statement best describes this process

Answers

Answer:

- The dry ice is cooling the ground it rests upon as heat is transferred from the ground to the dry ice.

Explanation:

The above statement correctly elaborates the process of using dry ice to develop the appearance of fog. When the dry ice is placed on the ground, the heat of the ground is transferred to the dry ice. This will result in the increase in the kinetic energy of the CO2 molecules. Thus, the solid will directly convert into gas and it will lead to the formation of gas in the air. Since CO2 possesses a higher density, it will look like fog and thus, giving the perfect shot for the fog scene.

Other Questions
The net income reported on the income statement for the current year was $240,000. Depreciation was $50,000. Accounts receivable decreased by $10,000 and inventories decreased by $30,000. Prepaid expenses increased by $1,000 and accounts payable increased by $8,000. How much cash was provided by operating activities? Select one: a. $337,000. b. $329,000. c. $301,000. d. $321,000. What is the difference between reading a novel and watch the same novel as a film?A)The combination of visual effects, audio, and animation creates a new experience forthe audience when watching a movie.B)The readers have to imagine narrated by the writer; when watching the movie, thereaders can easily connect with the characters and story.C)Watching the movie creates a stronger impact compared to reading thestory.D) All of the choices Which is not a water quality monitoring parameter ?1. Habitat2. Turbidity 3.salinity 4. Ph level Produces proteins drop down menus ZA and ZB are vertical angles. If m A = (5x + 2) and mZB = (6x 12),then find the value of x. Identify the constant of proportionality from the table.X: 4, 5, 7, 9Y: 32, 40, 56, 72 a If a stationary body of water has a constant temperature from top tobottom it is most likely a(n)a. lakeb. pondC.oceand. lagoon Can you do this questions pls? Roanoke Company produces chocolate bars. The primary materials used in producing chocolate bars are cocoa, sugar, and milk. The standard costs for a batch of chocolate (1,827 bars) are as follows: Ingredient Quantity Price Cocoa 600 lbs. $0.40 per lb. Sugar 180 lbs. $0.60 per lb. Milk 150 gal. $1.70 per gal. Determine the standard direct materials cost per bar of chocolate. If required, round to the nearest cent. Write the complies number z=3-3i in trigonometric form 4. Which is an environmental factor that affects skin color in humans?A. number of linked genesB. number of genes inheritedC. amount of food consumedD. amount of sunlight absorbed Rebecca is comparing prices on toilet paper. Charmin has 18 rolls, each with 200 sheets, for $12.97. Angel Soft has 24 rolls, each with 425 sheets, for $19.98. Which is the better value? Find the area in the right tail more extreme than z=0.93 in standard normal distribution, rounded to three decimal places. Can anyone please help? What is the measure of angle x? hawkville's population is 2500 people. next year the town clerk expects the population to grow by 1.2%, how many new residents will hawkville have next year? True or False? The final step of manually reconciling a bank statement is comparing deposits noted on the statement against the office's records or receipts by making a check mark next to each correct number.Pls help will mark brainliest The sum of two numbers must be 24 or greater. The product of the two numbers must be less than 60. Which system of inequalities represents this situation?A {x+y24xy24xy help with 4b thank you. The correlation coefficient, r, between the prices of smartphones, x, and the number of sales of phones, y, equals 0.63.Select the statement which best describes the relationship between the price and sales.The value of r indicates that the number of sales decreases as the price decreases.The value of r indicates that the number of sales decreases as the price stays the same.The value of r indicates that the number of sales decreases as the price increases.The value of r indicates that the number of sales is not related to the price.I think its (C): The value of r indicates that the number of sales decreases as the price increases.