Which of the following solutions represents a good buffer system? a solution that is 0.10 mol L-1 NaOH and 0.10 mol L-1 KOH a solution that is 0.10 mol L-1 HCl and 0.10 mol L-1 NH4+ a solution that is 0.10 mol L-1 HF and 0.10 mol L-1 CH3COONa a solution that is 0.10 mol L-1 HCl and 0.10 mol L-1 KCl a solution that is 0.10 mol L-1 CH3COOH and 0.10 mol L-1 CH3COOLi

Answer:

1. The core electrons are 10

2. The valence electrons are 8

Explaination:

Core electrons are electrons located in  the inner shells of and atom.

Valence electrons are electrons located on the outermost shell of an atom

From the question given above, we obtained:

Ar (18) => [Ne] 3s²3p⁶

Recall

Ne (10) => 1s² 2s²2p⁶

Therefore,

Ar (18) => [1s² 2s²2p⁶] 3s²3p⁶

From the above illustration,

Inner shell (core shell) => 1s² 2s²2p⁶

Outermost shell (valence shell) => 3s²3p⁶

1. Determination of the core electrons

Inner shell (core shell) => 1s² 2s²2p⁶

Core electrons = 2 + 2 + 6

Core electrons = 10

2. Determination of the valence electrons

Outermost shell (valence shell) => 3s²3p⁶

Valence electron = 2 + 6

Valence electron = 8

Answer:

10 core electrons

8 valence electrons

Explanation:

Answer:   7.025959200000001

Explanation:

Explanation:

Since magnesium has an atomic number of 12, that means that it has 12 protons and 12 electrons when it is in normal state.

Answer:

12 protons

Explanation:

Answer:

This evidence includes fossilized bones, teeth, eggs, footprints, teeth marks, and even dung. When paleontologists compare a skeleton of a living bird to the fossilized skeleton of a non-bird theropod, like Sinornithosaurus, they see many similarities.

Explanation:

Answer:

When people think of dinosaurs, two types generally come to mind. There were the huge herbivores,

like Apatosaurus, with their small heads and long tails. There were also those fearsome carnivores,

like Tyrannosaurus rex, that walked on two legs and had a mouthful of teeth like kitchen knives.

Living Dinosaurs

These large dinosaurs are no longer around, but dinosaurs still live among us today. They are the

birds. It's difficult to imagine that a bird on your window sill and a T. rex have anything in common.

One weighs less than a pound. The other was the size of a school bus, tipping the scales at eight

tons. But for all their differences, the two are more similar than you might think. In fact, birds and T.

rex are close relatives. They all belong to a group of dinosaurs called theropods.

This is a cladogram, a "" showing the relationships among organisms. The group called dinosaurs includes the extinct dinosaurs

and all their living descendants. All its members, including living birds, descended from the very first dinosaur-their common ancestor.

That's why birds are a kind of dinosaur (just as humans are a kind of primate).

Skeletal Evidence

When paleontologists compare a skeleton of a living bird to the

fossilized skeleton of a non-bird theropod, like Sinornithosaurus,

they see many similarities. They both have a hole in the hipbone, a

feature that distinguishes most dinosaurs from all other animals.

This feature allows an animal to stand erect, with its legs directly

beneath its body. All theropod dinosaurs, including birds, have a

furcula, also known as a wishbone. Another shared characteristic is the presence of hollow bones.

Hollow bones reduce the weight carried by an animal. This feature enables the animal to run faster. It

probably also played a role in the evolution of flight.

thought to have evolved for flight. The discovery of more and more non-flying dinosaurs with feathers

disproved that explanation. For these dinosaurs, feathers may have served other functions, like

gliding, insulation, protection, and display. Feathers play that same role in many bird species today.

Based on the evidence of shared characteristics, scientists have concluded that birds are a type of

Birds are the only dinosaurs with the ability to fly. This is

very interesting to scientists who want to know when the

capability of flight emerged. To find out, some scientists

study the brains of bird and non-bird dinosaurs. Soft

tissue, such as brains, is almost never preserved in the

fossil record. What is preserved is the imprint the brain

left on the inside of the skull. Now scientists are using

computed tomography (CT) scanners to create

endocasts. These are detailed, three-dimensional

reconstructions of the interiors of fossilized skulls.

In a recent study, researchers were able to peer inside

the braincases of more than two dozen specimens.

"Technology allows us to look inside these specimens

without destroying them," says Dr. Amy Balanoff, a

Museum research associate. "It's a non-destructive way

to basically slice up a dinosaur brain. We look inside and see what it can tell us about the evolution of

the brain within dinosaurs. Most of us grew up thinking that dinosaurs had tiny brains, but actually

some had really big brains."

The endocasts allow Balanoff and other researchers to

explore the outer shape of the brain in more detail. In

addition, the casts also provide new information about

the volume and shape of different regions of the brain.

For example, scientists looked at a detailed view of the

dinosaur cerebrum, a region of the brain related to

cognition and coordination. They found that this region

was very large in non-bird dinosaurs closely related to

birds. Dr. Balanoff's research suggests that these

dinosaurs developed big brains long before flight and that

these bigger brains prepared the way for them to fly.

When examining skeletal, behavioral, and brain

evidence, scientists see that birds and non-bird dinosaurs

share many features. This helped them conclude that

dinosaurs aren't extinct after all. They're living among us today.

(Im a really fast Typer and Thinker)

Have a nice day

Explanation:

You have a solution that contains 36 g HCl dissolved in 64 g water

Molar mass HCl = 36.45 g/mol

Mol HCl in 36 g = 36 g / 36.45 g/mol = 0.9876 mol

Molar mass H2O = 18 g/mol

Mol H2O in 64 g = 64 g / 18 g/mol = 3.5556 mol

Total mol = 0.9875 + 3.5556 = 4.5431 mol

Mol fraction HCl = 0.9876 mol / 4.5431 mol = 0.2174

Mol fraction H2O = 3.5556 / 4.5431 = 0.7826

The answer should have 2 significant digits:

Mol fraction HCl = 0.22

Mol fraction H2O = 0.78

Mol fraction has no units.

THAT IS HELPFUL FOR YOU

PLEASE MARK ME AS A BRAINLIST

Answer:

Your answer will be (D).

Hope this helps!

Answer:

D

Explanation:

You can tell when a chemical change occurs if a gas is produced (bubbles), an odor is produced, if there is a color change, or if the surroundings get hotter or colder.

Answer:

arrow down is gravity

Explanation:

Answer: The person above me is right

Explanation:

Have a Great day!

Answer:

sorry wala din akong sagot niyan sorry talaga

Answer:

PCI3

Explanation:

It does not obey the octet rule on the nitrogen atom.

Answer:

5:1

Explanation:

The molecular formula of serotonin is C10H12N2O. Therefore, the ratio of C atoms to N atoms is 5:1, because you divide 10 and 2 by 2, and then you get 5:1.

Explanation:

Leopards have 32 teeth, 4 of which are long, pointed canine teeth. Canine teeth are used to kill prey. Other teeth are for cutting flesh and grinding bone

Before

P1 : 748 mmHg

V1 : 22.5 L

After

P2 : 725 mmHg

V2 : ?

748 mmHg / 22.5 L = 725 mmHg / V2

Cross Multiply...

748 mmHgV2 = 16312.5 mmHgL

748 mmHgV2 / 748 mmHg = 16312.5 mmHgL / 748 mmHg

V2 = 21.808155 L

V2 = 21.8 L (sig figs)

Answer:

B

Explanation:

the candle is hot so the first energy form should be heat. u could now just eliminate the rest but for further notice. the heat melts the wax in the candle, which is a physical change but also the thread is burning out which is a chemical change then light follows

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.

Hence, sound moves faster in a solid than in gases.

Learn more about speed of sound: https://brainly.com/question/15381147

Answer:

Transparent- air,water,sheet of plane glass,

Opaque- piece of rock,sheet of aluminium,mirror,wooden board,CD,umbrella,wall,sheet of carbon paper,sheet of cardboard

Translucent-sheet of polythene,sheet of cellophane,smoke,fog,wire

●Luminous- iron,lighted fluorescent tube,flame of gas burner, lighted torch,kerosene stove,sun,firefly

Non Luminous- water,air,rock,sheet of polythene,sheet of aluminium,mirror,wooden board,sheet of polythene,CD,smoke,sheet of plane glass,fog,wall,umbrela,sheet of carbon paper,cardboard sheet,cellophane sheet,wire,moon.

BRAINLIST PLS

Answer:

2.3)X10^13-Hz

Explanation:

What’s the frequency of radiation that has a wavelength of 13 um, about the size of bacterium?

a micro meter is 10^-6 meter

frequency of light times wavelength = c  the speed of light 3X10^8 M/sec

so

frequency times 13 X10^-6 =3X10^8  M/

so

FR3EQUENCY = 3X10^8/13X10-6

=(30/13)10^13 =2.3)X10^13-Hz

7 X

6

Answer:

purity and pressure affects boiling point

Answer:

methane and petrol okkkkkkkkkkkkkkkkkkk

Answer: (1) increase(2) increase (3) increase (4) increases(5) decrease

Explanation:so basically anything you do will make the reaction go faster except like increasing the activation energy for example

The correct answers are as follows

Hence Except Activation energy the reaction rate will increase

Learn more about reaction rate below.

https://brainly.com/question/24795637

#SPJ2

Answer:

Soap is effective as a cleaning agent because it is amphiphilic; it is partly polar and partly nonpolar. ... The sodium ion of the soap is replaced by one of these new ions, and the resulting salt is no longer soluble.

Soap seems to be amphiphilic, or partially polar as well as partially nonpolar, it works well as a cleaning agent. Several of these newfound ions take the place of such soap's sodium ion, rendering the salt insoluble.

Long chain fatty acids are salts of sodium and potassium that have a cleaning effect in the water. referred as soap They should be used as cleaning agents to get rid of oil and filth from garments and skin. As an illustration, stearic, oleic, as well as palmitic acids are used to create sodium stearate, sodium oleate, respectively sodium palmitate.

Cleaning agents, often known as hard-surface cleansers, are things that are used to get rid of debris from surfaces, such as dust, stains, foul odors, and clutter. Health, aesthetics, odor removal, and stopping the transfer of dirt and toxins to oneself or others will be among the goals of cleaning products.

Because soap can serve as an emulsifying agent, it would be a superior cleanser. An emulsifier has the ability to mix two immiscible liquids together.

To know more about soap

https://brainly.com/question/19033481

#SPJ2

The water would stand at a height of 1033.6 cm

If the mass of the mercury, m equals the mass of the water, m' at its height,h', then the weight of the mercury W equals the weight of the water, W'

So, W = W'

mg = m'g

ρV = ρ'V' where ρ = density of mercury = 13.60 g/cm³, V = volume of mercury = Ah where A = cross-sectional area of tube = 1.00 cm and h = height of mercury = 76.0 cm, ρ' = density of water = 1.00 g/cm³, V = volume of water = Ah' where A = cross-sectional area of tube = 1.00 cm and h' = height of water.

So, ρV = ρ'V'

ρAh = ρ'Ah'

h' = ρAh/ρ'A

h' = ρh/ρ'

Substituting the values of the variables into the equation, we have

h' = ρh/ρ'

h' = 13.60 g/cm³ × 76.0 cm/1.00 g/cm³

h' = 13.60 × 76.0 cm

h' = 1033.6 cm

So, the water would stand at a height of 1033.6 cm

Learn more about water height here:

https://brainly.com/question/15415820

Answer:

9

Explanation:

In a chemical equation, the subscript numbers next to each element's symbol tell us how many atoms of that element are in the substance. So, for example, in H₂O, there are 2 atoms of hydrogen since there is a "₂" next to the H.

What's next to our H in C₄H₉? It looks like "₉," so we can determine that there are 9 hydrogen atoms in C₄H₉ (which is butyl, by the way).

Hopefully that's helpful! :)

Answer:

A peninsula ( Latin: paeninsula from paene "almost" and insula "island") is a landform surrounded by water on most of its border while being connected to a mainland from which it extends.

Explanation:

CAN I GET BRAINLIEST

Answer:

When the results do not match the experimenter's predictions.

Answer:

5.627 × 1019 milliliters

Explanation:

is this what you wanted?

Explanation:

The difference between heat and thermal energy is that thermal energy is not in the process of being transferred; it is not in transit, but remains as part of the internal energy of the system; heat, on the other hand, is energy in transit, i.e. energy in the process of being transferred from a hotter system.

Answer:

Degradation of matter

Explanation:

Physical change is a temporary change.

Answer:

Explanation:

b