Answer:
chu papi
Explanation:
a solution of HCI contains 36 percent HCI,by mass and calculate the mole fraction of HCI in the solution?
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
help me. correct answer will be marked as brnlst
Answer:
PCI3
Explanation:
It does not obey the octet rule on the nitrogen atom.
SUPPER EASY WILL GIVE BRAINLIEST NEED HELP ASAP
7. Which
pocess is an example of a chemical
change?
A. Salt mixes with water and
dissolves.
B. An aspirin tablet is crushed into a fine
powder.
C. Water droplets form on the outside of a
cold drink glass.
D. An antacid tablet is added to water and
bubbles are produced.
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.
Help please witb this
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! :)
Plants exchange carbon dioxide, water, and oxygen with their surrounding environment through openings in their ________ called _________.
A.
leaves, xylem
B.
roots, guard cells
C.
leaves, stomata
D.
stems, sori
Seratonin is a neurotransmitter. The ratio of C atoms to N atoms is____
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.
What is a peninsula?
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
Argon (Ar): [Ne]3s23p6 core electrons valence electrons
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:
Bio fuel is a mixture of petrol and 20%——————
Answer:
methane and petrol okkkkkkkkkkkkkkkkkkk
2. Why was sud production used to assess the effectiveness of the synthesized soaps?
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.
What is Soap?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.
What is cleaning agent?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
Help pretty please :)
A burning candle demonstrates the following type of energy transformations.
A: chemical → heat → light
B: heat → chemical → light
C: electrical → light
D: chemical → electrical → light
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
A very long tube with a cross-sectional area of 1.00 cm2 is filled with mercury to a height of 76.0 cm. At what height would water stand in this tube if it were filled with a mass of water equal to that of the mercury? (The density of mercury is 13.60 g/cm3 and the density of water is 1.00 g/cm3.)
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
help! giving brainliest
Answer:
sorry wala din akong sagot niyan sorry talaga
What’s the frequency of radiation that has a wavelength of 13 um, about the size of bacterium?
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
what are two factors that affect the boiling point of water
Answer:
purity and pressure affects boiling point
13500 mL convert to milliliters of mercury
Answer:
5.627 × 1019 milliliters
Explanation:
is this what you wanted?
If 22.5 L of nitrogen at 748 mm Hg are compressed to 725 mm Hg at constant temperature. What is the new volume?
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)
An electron is present at an energy level with an energy of 5.44 x 10−19 J. After a second, the electron is present at an energy level with energy, 2.4 x 10−19 J. What most likely happened during the transition?
A photon of energy 7.84 x 10−19 J was released.
A photon of energy 3.04 x 10−19 J was released.
A photon of energy 7.84 x 10−19 J was absorbed.
A photon of energy 3.04 x 10−19 J was absorbed.
Answer:
Explanation:
b
leopard has canine teeth because
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
find the answer
science
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
Imagine that scientists have just discovered a non-bird dinosaur skeleton. They want to know whether the dinosaur was closely related to birds. What features in ...
might help them decide?
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
Identify whether the following changes would generally increase or decrease the reaction rate. (3 points)
• Increasing the concentrations of reactants (0.5 point):
• Increasing the temperature (0.5 point):
• Increasing the pressure (0.5 point):
• Shining light on the reaction (0.5 point):
• Increasing the activation energy (0.5 point):
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
Increase Increase Increase Increase DecreaseWhat is Reaction rate?It is the measure of the change in concentration of the reactants or the change in concentration of the products per unit time.The speed of a chemical reaction is the change in concentration of a substance divided by the time interval during which this change is observed.
What will happen to reaction rate if we do the following?The reaction rate will increase on Increasing the concentrations of reactants.The reaction rate will increase on Increasing the temperature. The reaction rate will increase on Increasing the pressure.The reaction rate will increase on Shining light on the reaction.The reaction rate will decrease on Increasing the activation energy .
Hence Except Activation energy the reaction rate will increase
Learn more about reaction rate below.
https://brainly.com/question/24795637
#SPJ2
Someone help pls this is due today
Answer:
arrow down is gravity
Explanation:
Answer: The person above me is right
Explanation:
Have a Great day!
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
Under what condition will the result of an experiment based on a hypothesis most likely lead to a new experimentation?
Answer:
When the results do not match the experimenter's predictions.
the atomic number of magnsium is 12 this means that that its nucleus must contain
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:
Which of the following does NOT involve a physical change?
Answer:
Degradation of matter
Explanation:
Physical change is a temporary change.
How many grams are in 0.39 moles of water
Answer: 7.025959200000001
Explanation:
Compare and contrast thermal energy and heat
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.