Question 1 (2 points)
Which option can be classified as a pure substance?

Question 1 options:

heterogenous mixture


solution


homogenous mixture


compound

Question 2 (2 points)
Law of conservation of mass states that:

Question 2 options:

matter is destroyed


matter does not change


matter is neither created nor destroyed


matter is created

Question 3 (2 points)
What is a property of bases?

Question 3 options:

all of the above


Sour taste


Slippery touch


Ability to form hydronium ions+

Question 4 (2 points)
Which property do solutions with low pH values have?


What does it mean to have a neutral pH? - Aseptic Health

Question 4 options:

have a -OH group


feels slippery


turns litmus paper blue


tastes sour

Question 5 (2 points)
How do the products of chemical reactions compare to their reactants?

Question 5 options:

The products often have completely different properties than the reactants.


The products are usually more toxic than the reactants.


The products usuallyhave more mass than the reactants.


The products usually have more atoms than the reactants.

Question 6 (2 points)
Which of the following is an example of a physical change?

Question 6 options:

Water freezing into ice.


A piece of wood burning.


A toy car rusting.


Zinc producing hydrogen gas when mixed with water.

Question 7 (2 points)
What might happen if you mixed a strong acid with an equally strong base?

Question 7 options:

You would see an explosive chemical reaction.


The base would destroy the acid.


You'd wind up with a pH-neutral salt and water.


The acid would destroy the base.

Question 8 (2 points)
In the equation shown, what are the reactants?

2H2+O2àH2O

Question 8 options:

Hydrogen and oxygen molecules (2H2 and O2 )


Ice crystals


Hydrogen atoms (H)


Water molecules (H2O)

Question 9 (2 points)
Which phrase most accurately describes a chemical change?

Question 9 options:

A change in form


A change in taste


A change on the molecular level


A change in appearance

Question 10 (2 points)
What does it mean when there is a physical change?

Question 10 options:

A new substance has been formed.


Matter has changed from one substance into a new substance.


Matter has changed size, shape or form


Matter has changed on the molecular level.

help pls ill give 20 points!

Answer:

wer

c=3.00×108 m/s (the speed of light in a vacuum) λ = wavelength in meters ν = frequency in Hertz (Hz) or 1s or s−1 .

Explanation:

I might be wrong also you don't have to give me brainliest save it for someone else who knows I might be wrong

Explanation:

A hydrogen atom has an atomic number of 1.

So it's proton number will always be 1.

A neutral hydrogen atom does not have any charge.

So it has the same amount of electrons as protons, which turns out to be also 1.

A neutral hydrogen atom has an atomic mass of ≈1.00794amu≈1amu.

To find the amount of neutrons, we take the proton number and subtract it from the mass number.

1−1=0

So a neutral hydrogen atom has no neutrons.

In summary,

A hydrogen atom has

1 proton

1 electron

0 neutrons

another way of explaining:

The number of protons is the atomic number, and the number of protons plus neutrons is the atomic mass. For hydrogen, the atomic mass is 1 because there is one proton and no neutrons. For helium, it is 4: two protons and two neutrons

Answer:

26,981539 u là khối lượng nguyên tử của AI

Explanation:

Howler and warnibers is answer

Answer:

22 electrons

Explanation:

correct answer correct answer correct answer

At the left side; the balanced half equation is:

[tex]\mathbf{2H_2O _{(l)} + 2e^- \to H_{2(g)} + 2OH^{-}_{(aq)}}[/tex]

At the right side, the balanced half equation is:

[tex]\mathbf{4OH^-_{(aq)} \to O_{2(g)} + 2H_2O_{(l)} + 4e^-}[/tex]

The objective of this question is to determine the balanced half-reaction for the electrodes on the left and the right side.

A half-reaction is an oxidation-reduction reaction part of a redox reaction where we make sure both half-reactions are balanced by multiplication of the reactions with appropriate numbers in order to have an equal number of electrons.

According to the given information:

The overall cell reaction can be expressed as:

[tex]\mathbf{H_2O_{(l)} \to H_{2(g)} + \dfrac{1}{2}O_{2(g)}}[/tex]

At the left side; the balanced half equation can be expressed as:

[tex]\mathbf{2H_2O _{(l)} + 2e^- \to H_{2(g)} + 2OH^{-}_{(aq)}}[/tex]

At the right side, the balanced half equation can be expressed as:

[tex]\mathbf{4OH^-_{(aq)} \to O_{2(g)} + 2H_2O_{(l)} + 4e^-}[/tex]

Learn more about the electrolysis of water here:

https://brainly.com/question/22352373?referrer=searchResults

The mass of ferric nitrate, Fe(NO₃)₃ produced from the reaction given the data is 5792.44 g

2Fe + 6HNO₃ –> 2Fe(NO₃)₃ + 3H₂

Molar mass of Fe = 56 g/mole

Mass of Fe from the balanced equation = 2 × 56 = 112 g

Molar mass of Fe(NO₃)₃ = 56 + 3[14 + (16×3)] = 242 g/mole

Mass of Fe(NO₃)₃ from the balanced equation = 2 × 242 = 484 g

SUMMARY

From the balanced equation above,

112 g of Fe reacted to produce 484 g of Fe(NO₃)₃

From the balanced equation above,

112 g of Fe reacted to produce 484 g of Fe(NO₃)₃

Therefore,

1340.4 g of Fe will react to produce = (1340.4 × 484) / 112 = 5792.44 g of Fe(NO₃)₃

Thus, 5792.44 g of Fe(NO₃)₃ were obtained from the reaction

Learn more about stoichiometry:

https://brainly.com/question/14735801

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Answer:

Must be stable and relatively insoluble in boiling water.

Explanation:

it must be stable and relatively insoluble in boiling water and a must-have vapor pressure in boiling water that is of the order atmosphere at or more compound satisfy these conditions that will generally not separate from each other but we'll be separated from everything else.

Answer:

This page looks at the manufacture of alcohols by the direct hydration of alkenes, concentrating mainly on the hydration of ethene to make ethanol.

The steps in the ethanol production process include milling the corn to meal, liquefying the meal by adding water and cooking, breaking down starch into sugar, using yeast to ferment the sugar to ethanol, distilling the ethanol by boiling off and condensing it by removing residual water and finally denaturing so that...

Answer:

some example includes:

gold, copper, oxygen, chlorine, diamond

Explanation:

120°

Bent molecular geometry

Examples H2O, SO2

Point group C2v

Coordination number 2

Bond angle(s) 90°<θ<120°

Answer:    

Darwin observed   many  different   types of mockingbirds and finches lived in different island environments.

Answer:

The original marshmallow was named for the inclusion of marshmallow root in the recipe. The roots and leaves of the marshmallow plant contain mucilage, a slimy-textured demulcent best known for its use as a homeopathic cough suppressant. Marshmallow root is considered to be soothing and mildly antimicrobial. It has long been used as an herbal treatment for minor digestive issues and skin irritations, although its use in the creation of its namesake confection has long since fallen by the wayside.

Explanation:

So basically salt makes it strecthy! Please mark brainliest!!

CN- is the molecule which contains a covalent bond in this scenario.

This is the type of bond formed as a result of sharing of electrons between atoms of elements.

It exists in the reaction between compounds between two electronegative elements such as carbon and nitrogen to form cyanide.

Read more about Covalent bond here https://brainly.com/question/3447218

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Answer:

36 eggs

Explanation:

12 eggs in each carton

12 + 12 + 12 = 36 eggs

or 3 * 12 = 36 eggs

Hope this helps, have a nice day/night! :D

Answer:

The atmosphere is the superhighway in the sky that moves water everywhere over the Earth. Water at the Earth's surface evaporates into water vapor which rises up into the sky to become part of a cloud which will float off with the winds, eventually releasing water back to Earth as precipitation.

Explanation:

If you don't want to plagiarize change it up a bit.

Answer:

Hence, the wavelength of the photon associated is 1282 nm.

Explanation:

Answer:

Thermal energy consists of the total internal kinetic energy of an object due to the random motion of its atoms and molecules. It is related to heat and temperature.

Explanation:

Considering the ideal gas law, a sample weighing 9.49 g occupies 68.67 L at 353 K and 2.00 atm.

Ideal gases are a simplification of real gases that is done to study them more easily. It is considered to be formed by point particles, do not interact with each other and move randomly. It is also considered that the molecules of an ideal gas, in themselves, do not occupy any volume.

An ideal gas is characterized by three state variables: absolute pressure (P), volume (V), and absolute temperature (T). The relationship between them constitutes the ideal gas law, an equation that relates the three variables if the amount of substance, number of moles n, remains constant and where R is the molar constant of the gases:

P× V = n× R× T

In this case, you know:

Replacing:

2 atm× V = 4.745 moles× 0.082[tex]\frac{atmL}{molK}[/tex]× 353 K

Solving:

V = (4.745 moles× 0.082[tex]\frac{atmL}{molK}[/tex]× 353 K)÷ 2 atm

V= 68.67 L

Finally, a sample weighing 9.49 g occupies 68.67 L at 353 K and 2.00 atm.

Learn more:

Answer:

8 electrons.

Explanation:

Answer:

We assume that there is 100g of the compound (because it makes it easier to calculate) and we turn the percentages into grams.

2% of Hydrogen = 2g of H

32.7% of Sulfur = 32.7g of S

65.3% of Oxygen = 65.3g of O

Now we change the mass of these elements to moles by dividing the mass by the molar mass (which is the value of atomic mass on your periodic table)

2g/1.01g = 1.98 mol

32.7g/32.06g = 1.02 mol

65.3g/16g =4.08 mol

divide all these mol values by the smallest mol value, which is 1.02. (Round the values to whole numbers)

1.98/1.02 = 2 (rounded) of Hydrogen

1.02/1.02 = 1 of Sulfur

4.08/1.02 = 4 of Oxygen

H2SO4 (also known as sulphuric acid) is your empirical formula.

Answer:

AgCl

Explanation:

Got correct on E2020

Answer:

B: AgCl

Source: trust me bro

Answer:

a table is a grid of rows and columns that intersect to form cells

Explanation:

D or A im not fully sure about my answer on that

To solve for number one we must follow these steps:

m = 703.55 g − 345.8 g

m = 357.75 g

Then we solve for the density-

d = 357.75 g / 225 mL

d = 1.59 g/mL

Answer for number 5) 1.59 g/mL

Density= Mass/Volume

therefor- Mass = 65.14g and Volume = 35.4mL

Density = 65.14g/35.4 mL = 1.84 g/mL

Answer for number 6) 1.84 g/mL

Question 7-

g = (0.8765 g/mL)(250.0 mL) = 219.1 g

Answer: 219.1 g

Question 8-

Density = mass/volume

Mass = 1587g

4.5cm x 5.2cm x 6cm = 140.4 cubic-cm

Volume = 140.4 cubic-cm

Mass/volume = 1587/140.4 = 11.3 g/cm^3

Answer: 11.3 g/cm^3

Question 9:

First calculate the volume of iron

49.10mL − 45.50mL = 3.60mL

Density = mass/volume;

density = 28.5g/3.60 mL= 7.92 g/mL

Answer: 7.92 g/mL

Question 10:

Volume = 2500.0g / 10.5g/cm3 = 238.095cm^3

Now we round up the answer to 238cm^3

Answer: 238cm^3

I hope this helped!

Answer:

Remove a H2 molecule from the left side of the equation.

Explanation:

i took the quiz and got it right

Answer:

Strong affinity of HCl gas for moisture in air results in forming of droplets of liquid solution which appears like a cloudy smoke.

Explanation:

#followformore

Hope this helps :)