Answers
Related Questions
How many moles are in a sample of 2.39 x 10^23 atoms of sodium (Na)
Answers
Answer:
The answer is 0.4 molesExplanation:
To find the number of moles in a substance given it's number of entities we use the formula
[tex]n = \frac{N}{L} \\ [/tex]
where n is the number of moles
N is the number of entities
L is the Avogadro's constant which is
6.02 × 10²³ entities
From the question we have
[tex]n = \frac{2.39 \times {10}^{23} }{6.02 \times {10}^{23} } \\ = 0.39700996...[/tex]
We have the final answer as
0.4 molesHope this helps you
Calculate the heat that must be supplied to
a 532 , stainless steel vessel containing 375 g
of water to raise its temperature from 35 C
to the boiling point of water 100°C. Cs. =0.51 J/g. degrees C
Answer in units of J.
Answers
Q must be supplied = 119523.3~J
Further explanationThe law of conservation of energy can be applied to heat changes, i.e. the heat received/absorbed is the same as the heat released
Q in = Q out
Heat can be calculated using the formula:
Q = mc∆T
Q = heat, J
m = mass, g
c = specific heat, joules / g ° C
∆T = temperature difference, ° C / K
So from the question :
Q to the system(Q supplied) = Q water + Q steel vessel(Q gained)
[tex]\tt Q~supplied=m.c\Delta T(water)+m.c\Delta T(vessel)\\\\Q~supplied=375\times 4.18\times (100-35)+532\times 0.51(100-35)\\\\Q~supplied=101887.5+17635.8=119523.3~J[/tex]
ANSWER ASAP PLEASE!!
What determines how many of each ion is required for an ionic compounds?
please do not look up on google!!!!
Answers
Each ion has a single charge, one positive and one negative, so we need only one ion of each to balance the overall charge. When writing the ionic formula, we follow two additional conventions: (1) write the formula for the cation first and the formula for the anion next, but (2) do not write the charges on the ions.
Michelle learns in science class that simple machines such as an inclined plane can change the amount of force needed to lift heavy objects. She decides to test this with an experiment.
Michelle chooses a 10 kg weight. She sets up a ramp made of smooth metal that makes an angle θ with the floor. She attaches a spring scale to the weight and the top of the ramp in order to hold the weight in place. She records the force from the spring scale, then changes θ and records it again. She repeats this several times.
In this experiment, what is the dependent variable?
A.
the mass of the weight
B.
the angle θ between the ramp and the ground
C.
the amount of force on the spring scale
D.
the material the ramp is made of
Be fast please
Answers
Volcanic belts form along
a.
islands in the Pacific Ocean.
b.
North American mountain ranges.
c.
the boundaries of Earth’s plates.
d.
the coast of Antarctica.
Please select the best answer from the choices provided
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You are conducting an experiment with two very reactive substances. One will react with oxygen (O) and other substances in the air, and the other will react to metal in a container. What type of environment can you seal them in so they only react with each other?
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Answer:
seal them in a glass container in an atmosphere of argon (Ar) gas
Explanation:
Identify the property of the matter described below.
Alcohol floats on top of the water.
A-pH
B-conductivity
C-density
D-luster
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Answer: C.
Explanation: Alcohol floats on oil and water sinks in oil. Water, alcohol, and oil layer well because of their densities, but also because the oil layer does not dissolve in either liquid. The oil keeps the water and alcohol separated so that they do not dissolve in one another. ... Water sinks because it is more dense than oil.
colonel flanders makes boxes of chicken with various numbers of pieces. He charges $ 0.40 for each piece of chicken, plus a fixed charge of $ 0.55 for the box, the rolls, etc. If Iddy Ottic bought the $6.95 box, how many piecesof chicken should the box contain?
Answers
Subtract 0.55 from 6.95 and you get 6.40
The divide 6.40 by 0.40 and you get 16
25 cm of liquid 'A' and 20 cm of liquid
'B' are mixed at 25°C and the volume of
solution was measured to be 44.8 cm3
then correct reaction is
(A) A Hmix = 0, solution shows
ideal
Answers
Answer:
The correct option is;
(B) [tex]\Delta H_{mix} < 0[/tex], solution shows negative deviation
Explanation:
The given parameters are;
The available volume of liquid A = 25 cm³
The available volume of liquid B = 20 cm³
The volume of the solution (mixture) = 44.8 cm³
Therefore, we have;
[tex]\Delta _{mix} V < 0[/tex]
Which is one of the prerequisite for the formation of negative deviation
When a non-ideal solution shows negative deviation according to Raoult's Law, we have;
[tex]\Delta _{mix} H < 0[/tex], we have more heat released due to new molecular interactions.
Why are biopharmaceuticals in high demand?
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Answer:
the market is largely driven by the growing population, increasing burden of chronic disease, and rising inclination toward targeted therapy.
Explanation:
also, the huge demand of biopharmaceutical is facilitated by an accelerating focus in research and related investment.
True or False: A Precipitate is a solid
that forms out of a liquid solution as a
result of a chemical reaction
Answers
Answer:
true because it undergoes a tranformation
Explanation:
What explains the structure of metals and delocalized electrons?
A. the unit cell model
B. the geometric shape model
C. the covalent bond model
D. the electron sea model
Answers
Which statement best explains why the air pressure is greater at the poles than at the equator
Answers
Answer:
At the equator, the altitude is lower, and also because of the direct heating of sun rays on the surface, the temperature is much higher than at the poles. This makes the air near the surface hot and lighter and hence it rises up which results in lower air pressure.
Explanation:
Plz give me brainliest .-.
Which of the following is the correct model of C7H16?
A.
B.
C.
D.
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Answer:
D
Explanation:
Option D gives the correct model of C7H16. From the option, one will discover that the model has 7 carbons in the backbone. If you count the attached hydrogen, you will discover that the hydrogen is 16 in total.
This model or skeletal structure of this element represents heptane. Heptane or n-heptane is known to be a straight-chain compound and an alkane. It's chemical formula can also be written as: H₃C(CH₂)₅CH₃ or C₇H₁₆.
This compound is known to be one of the main components of gasoline. It is known to be a volatile organic compound and a clear and colorless liquids with a petroleum-like odor.
Answer: D
Explanation: Just took the test
Do you guys have viruses wit this website
Answers
What kinds of paintings did Winslow Homer make
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He was best known for drawing,
Wood engravings
Oil painting
Water color painting.
Mostly self-taught, Homer is known for the visceral force of the waves in his oil paintings, but his watercolors are an antidote to any visual heaviness and weight. As his early paintings reveal, watercolor is where he shined as an artist with a graceful, innovative hand.
Have a great day :)
Which has a smaller ionic radius than it's neutral atom?
A. Iodine
B.Cesium
C.Oxygen
D.Nitrogen
Answers
Explanation:
Caesium (Cs) has a smaller ionic radius than it's neutral atom.
because Caesium belong to Group 1 and It loses 1 electron. After losing 1 electron it gains 1 positive charge that's why caesium ionic radius become smaller as compared to neutral atom.
Therefore,
Option B is correct.
stages of mitosis in order
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Answer:
nucleus formed
prophase
metaphase
anaphase
telophase and cytokinesis
What is force and motion
Answers
Answer:
In physics, a force is any interaction that, when unopposed, will change the motion of an object. A force can cause an object with mass to change its velocity (which includes beginning moving from a state of rest), i.e., to accelerate. Force can also be described intuitively as a push or a pull.
lol
How does the valence electron configuration (entire last energy level configuration) relate to the group number on the Periodic Table? Use the shorthand notation in your discussion.
Answers
Answer:
The valence electron configuration determines the group to which an element belongs to.
Explanation:
The valence electron configuration of an atom of an element refers to the number of electrons in that atoms outermost shell.
The valence electron configuration is related to the group number of an element in that the number of electrons in the valence shell of an atom of an element determines the group to which an element belongs to. For example, all elements having one valence electron belong to group IA of the periodic table. Similarly, all elements having seven valence electrons belong to group VIIA of the periodic table.
This is because, since the reactivity of an element is related to its ability to either gain or lose a certain number of electrons in its valence shell, elements having same number of valence electrons have similar chemical properties.
During the Metric Olympics yesterday, Molly's long jump was 118.3 cm. Christy accidentally recorded her results in inches. She jumped 51.18 inches. Can you help... Who won the long jump? Christy won by about 30 cm Christy won by about 30 cm Molly won by about 25 cm Molly won by about 25 cm Christy won by about 12 cm Christy won by about 12 cm Molly won by about 10 cm
Answers
Answer: Christy won Molly by 12cm
Explanation:
Ist step
Molly's ;ong jump was 118.3cm
Christy long jump was 51.18inches
2nd Step
we change christy score to cm so we can compare
1 inch = 2.54cm.
therefore 51.18 inches = 51.18 x 2.54= 129.9972cm
Christy won molly by 129.9971cm-118.3cm=11.69 rounded to 12cm
Christy won Molly by 12cm
If the density of a substance is 2.18 g/mL, how would you find the density given that the mass is 0.987 kg and the volume is 4.52 x 102 mL?
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Answer:
Explanation:
Convert mass in gms .. 987 gms
Density = mass/ volume
= 987/4.52 x102
= 2.18 g/mL
Which types of matter are made of atoms
a. Mixtures
b. Elements
C. Compounds
D. All of the above
Answers
Answer:
D all above yes I think it's all above
Answer: D
Explanation: All of the above.
Plz mark brainliest:)
Would love some help pleaseee. and please at least read the question instead of skipping it please.
Measuring tools can have errors. Errors lead to ___________________ results and _______________ conclusions. To calculate the difference of the accepted value and the experimental value, scientists use this formula:
percent error = (experimental value − ) × 100. accepted value
Minimizing Bias
People show bias when they want everyone to accept their results. Bias can arise for many reasons:
• Companies show bias when they depict only the research details that are in the best interest of their ____________.
• Scientists may be biased toward their _____________ and modify results suit their needs.
• Scientists may also show to bias get their research published in ______________ ______________.
Such biases often lead to _______________ facts. An important part of scientific thinking is identifying biases and taking the necessary steps to minimize them.
For results to be considered scientifically accurate, any scientist, regardless of his or her own bias, should be able to replicate the experiment and get the same results.
Summary
Think of some studies you’ve heard about. How can you tell whether the studies were well-designed and scientifically accurate or had biases?
Answers
Answer: this looks like your homework
Explanation:if you want help you are going to have to ask a specific question instead of giving people your homework.
Answer:
Honestly I would search this up maybe there might be a pdf with the answers. Sorry chemistry isn't my thing:(
Explanation:
choose the letter that best describes the behavior of a substance during a phase change:
/A/ neither absorbs or releases energy
/B/ always absorbs energy
/C/ always releases energy
/D/ either absorbs or releases energy
Answers
Answer:
/D/ either absorbs or releases energy
Explanation:
During a phase change energy is either absorbed or released.
A phase change is a reversible process which occurs when a substance changes is its state from one form to another.
Phase changes are used to delineate physical changes.
A phase diagram provides a graphic representation of the change. The diagram can be 2 dimensional or 3 dimensional.What is a system?
A. An isolated piece of the world
OB. A liquid in which reactions take place
O C. A piece of scientific equipment
O D. A technique for recording data
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Answer:
D. a technique of recording data
When many earthquakes are studied, there is another common pattern that emerges: a "Shadow Zone". This is an area, for any earthquake, on the Earth where direct S-waves don't arrive at all and P waves are refracted. What do you think causes these P waves to be refracted? *
Answers
Answer:
Sudden decrease in the velocity at the boundary.
Explanation:
The shadow zone is the zone of the earth from angular distances of 104° to 140° from a known earthquake that does not directly receive any P waves. Now, this shadow zone occurs as a result of S waves getting stopped completely by the liquid core and the P waves being refracted by the liquid core.
From earlier seismic discoveries, this boundary which is the shadow zone that does not directly receive any P-waves was found to be due to the fact that the P-waves were refracted inwards as a result of the sudden decrease in velocity at the boundary.
What is the mass of an object with a density of 5.7 g/cm^3 and a volume of 48
cm^3? *
Answers
Answer:
273.6 g
Explanation:
mass =(density)(volume)
mass=(5.7g/cm^3 )(48 cm^3)
cancel out your cm^3 and your are left with grams
multiply (5.7g)(48)=273.6 g
The mass of an object with a density of 5.7 g/cm³ and a volume of 48 cm³ is 273.6 grams.
What is density?Density is defined as the degree to which a material is packed together.
It is also defined as a mass per unit volume of the substance.
Its SI unit is kilogram per cubic meter or gram per meter.
Density can be expressed as
Density = mass / volume
Mass = density x volume
As given, Density = 5.7 g/cm³
Volume = 48 cm³
So, Mass = 5.7 g/cm³ x 48 cm³
= 273.6 grams
Thus, the mass of an object with a density of 5.7 g/cm³ and a volume of 48 cm³ is 273.6 grams.
To learn more about density, refer to the link below:
https://brainly.com/question/15164682
#SPJ5
a molecule for sulfur dioxide consists of one sulfur atoms (S) and two oxygen atoms (0). what is the chemical formula for this compound
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What is Arsenic cost per unit?
Answers
Answer:
arsenic costs $320 per 100g
Explanation: