The graph below shows the speed of a downhill
skier during a period of several seconds. Use the
graph to answer Question 13.
16
12
Speed (m/s)
8
0
1
3
3
2
Time (s)
13. Read Graphs What is the skier's acceleration?

Answer:

The freezing point is -3.72 degrees Celsius

Explanation:

In this question, by assuming the complete dissociation of the salt, we want to calculate the freezing point of an aqueous 1 M NaCl solution .

We proceed as follows;

Firstly, we write the dissociation equation;

NaCl ——> Na+ + Cl-

So the number of ions present in the dissociation is 2. This means that the Vant Hogg factor also called I = 2

Mathematically;

ΔTf = Kf*m*i

m represents the molality which is given as 1

So by substituting the values, we have;

ΔTf = 1.86 * 1 * 2 = 3.72 degrees Celcius

The freezing point however is 0 - ΔTf = 0 - 3.72 = -3.72 degrees Celcius

Answer:

Wind and Hydroelectricity can be considered forms of solar energy.

Explanation:

Wind power is a form of solar energy because winds are caused by the heating of the atmosphere by the sun, the rotation of the Earth, and the Earth's surface irregularities. For as long as the sun shines and the wind blows, the energy produced can be harnessed to send power across the grid.

Hydroelectricity is a form of solar energy because Hydropower relies on the water cycle.

The water cycle has three steps:

Solar energy heats water on the surface of rivers, lakes, and oceans, which causes the water to evaporate.

Water vapor condenses into clouds and falls as precipitation—rain and snow.

Precipitation collects in streams and rivers, which empty into oceans and lakes, where it evaporates and begins the cycle again.

Answer:

Self-reduction is a reaction in which no external reducing agent is required. It is called self-reducing because copper oxide itself reduced the copper sulfide to give copper and sulfur dioxide.

Answer:

To instill a high degree of personal honor, self-reliance, and confidence in each cadet by presenting a military environment in which cadets will be forced to rely upon themselves and their shipmates to study, work, and learn.

Answer:

all the below are ACIDS

Explanation:

1.HCOO- Formate

  HCOO- is a conjugate base.

2.HNO3- Nitric Acid

  Acid

3.CH3COOCH3: Methyl acetate

   Acid

4. HCOOH: Formic Acid

   Acid

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Answer:

Dobereiner could find only three triads; . i.e total of 9 elements only. However the total number of elements were more than that of those encompassed in Dobereiner's Triad

Explanation:

Answer:

Dobereiner could find only three triads; . i.e total of 9 elements only. However the total number of elements were more than that of those encompassed in Dobereiner's Triad. Thus, Dobereiner's could not be classify most of the elements known at that time

Explanation:

This work is not my own.... copied from google but hope this helps you.

Answer:

55.85 amu

Explanation:

Let A, B, C and D represent the four isotopes of element X.

The following data were obtained from the question:

Isotope A:

Abundance (A%) = 5.845%

Mass of A = 53.93961 amu

Isotope B:

Abundance (B%) = 91.75%

Mass of B = 55.93494 amu

Isotope C:

Abundance (C%) = 2.123%

Mass of C = 56.93539 amu

Isotope D:

Abundance (D%) = 0.2820%

Mass of D = 57.93328 amu

Average atomic mass of element X =.?

The average atomic mass of X can be obtained as follow:

Average Atomic mass = [(Mass of A × A%)/100] + [(Mass of B × B%)/100] + [(Mass of C × C%)/100] + [(Mass of D × D%)/100]

Average Atomic mass = [(53.93961 × 5.845)/100] + [(55.93494 × 91.75)/100] + [(56.93539 × 2.123)/100] + [(57.93328 × 0.2820)/100]

= 3.15277 + 51.32031 + 1.20874 + 0.16337

= 55.84519 ≈ 55.85

Therefore, the average atomic mass of X is 55.85 amu

Answer:

Silicon tetrachloride

Dinitrogen tetroxide

The name of the compound SiCl₄ is named silicon tetrachloride and N₂O₄ is named dinitrogen tetroxide.

SiCl₄ is named silicon tetrachloride. It is composed of one silicon atom (Si) bonded to four chlorine atoms (Cl). The prefix "tetra-" indicates the presence of four chlorine atoms bonded to the central silicon atom.

N₂O₄ is named dinitrogen tetroxide. It consists of two nitrogen atoms (N) bonded to four oxygen atoms (O). The prefix "di-" indicates the presence of two nitrogen atoms, and the suffix "-tetraoxide" indicates the presence of four oxygen atoms.

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Answer:

Aye Wassup? Adam Here :D

Explanation:

Nitrogen dioxide is a chemical compound with the formula NO 2.It is one of several nitrogen oxides. NO 2 is an intermediate in the industrial synthesis of nitric acid, millions of tons of which are produced each year for use primarily in the production of fertilizers.At higher temperatures it is a reddish-brown gas.

Hope This Helped Bro: "AdamDaAssasin"

Answer:

[tex]Ksp=[Zn^{2+}]^3[PO_4^{3-}]^2[/tex]

Explanation:

Hello,

In this case, since the equilibrium dissociation of zinc phosphate is:

[tex]Zn_3(PO_4)_2(s)\rightleftharpoons 3Zn^{2+}(aq)+2(PO_4)^{3-}(aq)[/tex]

Due to the fact that only the zinc and phosphate ions are in aqueous state, the solubility product expression is written considering the law of mass action in which the concentration of each species is powered to the corresponding stoichiometric coefficient as follows:

[tex]Ksp=[Zn^{2+}]^3[PO_4^{3-}]^2[/tex]

Best regards.

Answer:

The answer is

Explanation:

In order to calculate the volume needed we use the formula

[tex]V_2 = \frac{C_1V_1}{C_2} [/tex]

where

C1 is the concentration of the stock solution

V1 is the volume of the stock solution

C2 is the concentration of the diluted solution

V2 is the volume of thevdiluted solution

From the question

C1 = 1.45 M

V1 = 25 mL

C2 = 0.0245 M

So we have

[tex]V_2 = \frac{1.45 \times 25}{0.0245} = \frac{36.25}{0.0245} \\ = 1479.59...[/tex]

We have the final answer as

Hope this helps you

Answer:

128 neutrons

Explanation:

How many neutrons are there in 8 molecules of [tex]^{19} _9 F_2[/tex]?

Step 1: Calculate the number of neutrons in 1 atom of F.

The atomic number (z) of F is 9 and its mass number (A) is 19. We can calculate the number of neutrons using the following expression.

n⁰ = A - Z = 19 - 9 = 10

Step 2: Calculate the number of neutrons in 1 molecule of F₂.

1 molecule of F₂ contains 2 atoms of F. The number of neutrons in  1 molecule of F₂ is:

(8 n⁰/1 atom F) × (2 atom F/1 molecule F₂) = 16 n⁰/1 molecule F₂

Step 3: Calculate the number of neutrons in 8 molecules of F₂

8 molecule F₂ × 16 n⁰/1 molecule F₂ = 128 n⁰

Answer:

Living organisms breathe gases in the atmosphere.

Explanation:

Answer:

Living organisms breathe gases in the atmosphere.

Explanation:

Biosphere

the regions of the surface, atmosphere, and hydrosphere of the earth (or analogous parts of other planets) occupied by living organisms.

 Atmosphere

the envelope of gases surrounding the earth or another planet

Matter are anything that is made up of atoms. The quantity of matter can be observed only on the basis of mass and volume calculation. Therefore, the correct option is option C.

Matter is a substance that has some mass and can occupy some volume. The matter is mainly used in science. Matter can be solid, liquid or gas.

Matter is anything that is made up of atoms. Anything around us that can be physically seen and touched are matter. Ice, water and water vapors are example of matter.

Cytosol is the liquid medium contained within a cell. The cytosol is a component of the cytoplasm. Out of given option cytosol  has the greatest concentration of potassium ions. The cytoplasm does not include the nucleus.

Therefore, the correct option is option C.

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Answer: 343 K

Explanation:

To convert Celsius to Kelvin, you would add 273 to Celsius.

70°C+273=343 K

Now, we know that 70°C is 343 K.

Answer:

Mass and density is the answer?

Answer: James Chadwick discovered neutral particles in the nucleus. So your answer is C

Explanation:

I just took a pretest and I had this same question and I got it right

Answer:

James Chadwick discovered neutral particles in the nucleus.

Answer: biotic is Living things in their ecological relations.

Explanation:

Answer:

1.03

Explanation:

You would take 0.00103 and move the decimal like this; 0001.03, we wouldn't have the zeroes in front of the one, as it can throw us off. Therefore, your answer would be 1.03.

Hope I helped! Don't hesitate to let me know if I made a mistake.

Answer:

Explanation:

Pellet form of NaOH is highly hygroscopic . It absorbs moisture from air and its weight is increased by the time one tries to weigh one gram of it . Moreover it also reacts with carbon dioxide gas of atmosphere to form sodium carbonate .

2 NaOH + CO₂ = Na₂CO₃ + H₂0.

It also increases its weight .

-78° Celsius is the temperature in units of degrees Celsius.

Temperature is the measure of hotness or coldness expressed in terms of any of several scales, including Fahrenheit and Celsius.

195 Kelvin = 195 - 273.15 = -78.15 Celsius.

-78° Celsius is the temperature in units of degrees Celsius.

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Answer:

344.5764 torr

Explanation:

Molar mass of naphthalene = 128.2g/mol

Mass of naphthalene = 10.60 g

Carbon disulfide:

Molar mass= 76.14g/mol ;

volume = 155mL ;

density = 1.261 g/mL

Vapour pressure = 355.6 torr

Number of moles = mass / molar mass

CS2:

Mass = density × volume

Number of moles = (density × volume) / molar mass

Number of moles = (1.261 * 155) / 76.14 = (195.455 / 76.14) = 2.567 moles of CS2

Number of moles of C8H10:

Number of moles = 10.60 / 128.2 = 0.083 C8H10

Total number of moles :

2.567 + 0.083 = 2.65 moles

Mole fraction of each compound in solution :

CS2 :

2.567 / 2.65 = 0.969

C8H10:

0.083 / 2.65 = 0.031

According to Raoult's:

Psolution = Xsolvent × Posolvent

CS2 = solvent

Xsolvent = Mole fraction of solvent

Posolvent = Vapour pressure of pure solvent

Psolution = 0.969 × 355.6 torr = 344.5764 torr

The vapor pressure of the solution would be as follows:

[tex]344.5764[/tex] torr

Given that,

Vapor pressure of Carbon Disulfide [tex]= 355.6[/tex] torr

[tex]volume = 155mL ;[/tex]

[tex]density = 1.261 g/mL[/tex]

Naphthalene's mass [tex]= 10.60 g[/tex]

Naphthalene's molar mass [tex]= 128.2g/mol[/tex]

Now,

We know that

Number of moles [tex]= mass/molar mass[/tex]

Mass [tex]= density[/tex] × [tex]volume[/tex]

[tex]Number of moles =[/tex] [tex](density[/tex] × [tex]volume) / molar mass[/tex]

So,

Number of moles of Carbon Disulfide [tex]= (1.261[/tex] × [tex]155) / 76.14[/tex]

[tex]= (195.455 / 76.14)[/tex]

[tex]= 2.567[/tex] moles of Carbon Disulfide

Number of moles of Naphthalene:

Number of moles [tex]= 10.60 / 128.2[/tex]

[tex]= 0.083[/tex]

Now,

Total number of moles :

[tex]2.567 + 0.083[/tex]

[tex]= 2.65[/tex] moles

Mole fraction of each compound in solution :

Carbon Disulfide:

2.567 / 2.65

[tex]= 0.969[/tex]

Naphthalene

0.083 / 2.65

[tex]= 0.031[/tex]

According to Raoult's:

P[tex]solution = Xsolvent[/tex] × [tex]Posolvent[/tex]

Carbon Sulfide = Solvent

[tex]Xsolvent =[/tex] Mole fraction of solvent

[tex]Posolvent =[/tex] Vapour  pressure of the pure solvent

[tex]Psolution[/tex] [tex]= 0.969[/tex] × [tex]355.6 torr[/tex]

[tex]= 344.5764[/tex] torr

Thus, "[tex]344.5764[/tex] torr" is the correct answer.

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Answer:

0.71 gal

Explanation:

Step 1: Given data

Density of Diesel (ρ): 0.839 g/mL

Mass of Diesel (m): 2.3 kg

Step 2: Convert "m" to grams

We will use the relationship 1 kg = 10³ g.

2.3 kg × (10³g/1 kg) = 2.3 × 10³ g

Step 3: Calculate the volume (V) of the Diesel sample

We will use the density formula.

ρ = m/V

V = m/ρ

V = 2.3 × 10³ g/(0.839 g/mL)

V = 2.7 × 10³ mL

Step 4: Convert "V" to L

We will use the relationship 1 L = 10³ mL.

2.7 × 10³ mL × (1 L / 10³ mL) = 2.7 L

Step 5: Convert "V" to gal

We will use the relationship 1 gal = 3.79 L.

2.7 L × (1 gal/3.79 L) = 0.71 gal

Answer:

2.3 kg x1000 g/kg = 2300 g

2300 g x 1 ml/0.839 g = 2741 ml

2741 ml x 1 L/1000 ml = 2.741 L

2.741 L x 1 gal/3.79 L = 0.72 gallons

Explanation:

Answer:

72 million because they needed to raise cash for its development

Explanation:

It is a known fact that at lunch Ethereum had only 72 million tokens in existence back in July 2015. In other to develop the Blockchain network further, the founder, Vitalik Buterin organized a fundraising event around July and August 2014.

Fast forward to the year 2020, Ether now has a total supply of about 112 million.

Answer:

[tex]V=0.200L[/tex]

Explanation:

Hello,

In this case, since the volumetric capacity of the beaker is 200 cm³, by considering that 1000 cm³ equals 1 L, the liters are then computed via the following unit conversion:

[tex]V=200cm^3*\frac{1L}{1000cm^3}\\ \\V=0.200L[/tex]

Best regards.

Answer:

buoyancy. ...

Explanation:

........

Answer:

buoyancy

Explanation:

mark as brainliest

Answer:

The correct option is (D).

Explanation:

Uncertainty means lack of certainty in any calculations. It is the quantification of doubts after the calculations are done.

In this problem, we need to find the uncertainty in the measurement 0.0035 mg. There are 4 numbers after decimal. It means uncertain digit 1/10000 is the smallest scale division.

Hence, the uncertainty in the measurement 0.0035 mg is +0.0001 mg

Answer:

C Qualitative Analysis.

Explanation:

Answer:

experiment showed that the atom is mostly empty space with a tiny, dense, positively-charged nucleus.

Explanation:srry im late but i dont be on it like that  hoped it helped tho srry

Answer:

a. control everything the cell does

Explanation:

the nucleus is like the brain of the cell