Each roman numeral represents a sample of a substance. Each circle represents an atom. Considering what qualifies as a pure substance, which image(s) would be considered pure substances?

III and V


V


II and IV


I and III

Answer:

13.7 cm

Explanation:

If the number is between two whole numbers then that means it is going to be a decimal, how to determine the decimal is by how many ticks/lines are between it, so if you count from 13 cm and count each line as 1 you get to the number 7 and since that number is between the whole number it becomes 13.7

Answer:

chemical potential enery

Mark brainliest

Answer:

the number of protons is called the atomic number

hope it helps you buddy

Answer: number of protons in an atom

Explanation:

Answer:

C)[D]/[ED] = 5.20

D)[D]/[ED] = 5.20

E)[D']_T = 1.495* 10 ^-7 M

F)[D'] / [ED']  = 0.0579

Explanation:

E = 250 nM =2.5* 10 ^-7 mol/L , T=298.15 K

Dissociation constant of K_D = 1.3 μM (1.3 *10 ^-6 M)

E + D ⇄ ED → K_a = [ED] / [D][E]   (association constant)

ED ⇄ E + D → K_D = [E][D] / [ED]  (dissociation constant)

C)

[E] =2.5*10^-7 mol/L

K_D = 1.3* 10^-6 M

K_D = [E][D] / [ED] → [D]/[ED] = K_D / [E]

= [D]/[ED] = 1.3* 10 ^-6 / 2.5 *10^-7

= 13/25 * 10

=130/25 = 5.20

[D]/[ED] = 5.20

D)

ΔG =RTln Kd

ΔG_2 for E and D = 1.987 * 298.15 * ln 1.3*10^-6

ΔG_2 592.454 * [ln 1.3 +ln 10^-6]

ΔG_1 = 592.424 [0.2623 - 13.8155]

ΔG_2 = -592.424 * 13.553

ΔG_1 = -8184.633 cal/ mol

ΔG_1 = -8184.633  * 4.18 J/mol = -34244.508 J?mol

ΔG_1 = -34.245 KL/mol

so, ΔG_2 = ΔG_1 - 10.5 KJ/mol

ΔG_2 = -34.245 - 10.5

ΔG_2 = -44.745KJ / mol

ΔG_2 =RT ln K_D

-44.745 *10^3

=8.314 *298.15 lnK_D

lnK_D' = - 44745 / 2478.81 g

ln K_D' = -18.051

K_D' = -18.051

K_D' = e^-18.051

[D]/[ED] = 5.20

E)

[E] = 2.5* 10 ^-7 mol/ L = a

K_D' = [E][D] / [ED']                                  E +D' → ED'

K_D' = a/2(x-(a/2) / (a/2)

KD' = x - a/2

=2.447 *10^-8 = (2.5/2) * 10^-7

x=2.447 * 10^-8 + 1.25 * 10^-7

x = 2.447 *10^-8 + 1.25 * 10 ^-7

x= 10^-7 [1.25 + 0.2447]

x = 1.4947 * 10^-7

[D']_T = 1.495* 10 ^-7 M

F)

K_D' = [E][D'] / [ED']

[D'] / [ED'] = KD' / [E]

[D'] / [ED'] = 1.447 *10^-8 / 2.5* 10^-7

[D'] / [ED'] = 0.5788 * 10^-1

[D'] / [ED']  = 0.0579

Explanation:

...

Answer:

7790

Explanation:

Answer:

7790 decigrams

Explanation:

Answer:

[tex]\boxed {\boxed {\sf 1.87 \J/g \textdegree C}}[/tex]

Explanation:

We are asked to find the specific heat capacity of a liquid. We are given the heat added, the mass, and the change in temperature, so we will use the following formula.

[tex]q= mc\Delta T[/tex]

The heat added (q) is 47.1 Joules. The mass (m) of the liquid is 14.0 grams. The specific heat (c) is unknown. The change in temperature (ΔT) is 1.80 °C.

Substitute these values into the formula.

[tex]47.1 \ J = (14.0 \ g) * c * (1.80 \textdegree C)[/tex]

Multiply the 2 numbers in parentheses on the right side of the equation.

[tex]47.1 \ J = (14.0 \ g * 1.80 \textdegree C)*c[/tex]

[tex]47.1 \ J = (25.2 \ g*\textdegree C) *c[/tex]

We are solving for the heat capacity of the liquid, so we must isolate the variable c. It is being multiplied by 25.2 grams * degrees Celsius. The inverse operation of multiplication is division, so we divide both sides of the equation by (25.2 g * °C).

[tex]\frac {47.1 \ J}{(25.2 g *\textdegree C)} = \frac {(25.2 g *\textdegree C)*c}{{(25.2 g *\textdegree C)}}[/tex]

[tex]\frac {47.1 \ J}{(25.2 g *\textdegree C)} =c[/tex]

[tex]1.869047619 \ J/g *\textdegree C = c[/tex]

The original measurements of heat, mass, and temperature all have 3 significant figures, so our answer must have the same. For the number we found that is the hundredth place. The 9 in the thousandth place to the right tells us to round the 6 up to a 7.

[tex]1.87 \ J/ g * \textdegree C =c[/tex]

The heat capacity of the liquid is approximately 1.87 J/g°C.

Answer:

Below

Explanation:

To convert calories to joules, you need to multiply the value by 4184

     450 x 4184 = 1882800 J

If your teacher requires you to round to significant figures, you would round to 2 sig figs as 450 only has 2 sig figs

     450 x 4184 = 1.9 x 10^6

Hope this helps! Best of luck <3

Answer:

Gas pressure is caused when gas particles hit the walls of their container. The more often the particles hit the walls, and the faster they are moving when they do this, the higher the pressure. This is why the pressure in a tyre or balloon goes up when more air is pumped in.

Answer:

The correct choice is option b. ethanol < Mg(NO3)2 < NaCl

Explanation:

Ethanol = 0.100 m

Mg(NO3)2 = 0.15 m

NaCl = 0.18 m

The molar concentration of NaCl is the highest, which is why its boiling point will be the highest, too.

[tex]\boxed{\sf {Ca(OH)_2(s)\atop Calcium\:Hydroxide}\longrightarrow {CaO(s)\atop Calcium\;oxide}+{H_2O(g)\atop water}}[/tex]

On reactant side

On product side

hence balanced.

Answer:

Divide by 1000

Explanation:

Have a good day

Hope I helped

Multiply by 1000 .

I HOPE IT WILL HELP YOU.

HOPE your day goes great.

Answer:

To find the number of neutrons in an isotope, subtract the number of protons from the atomic mass of the isotope. The atomic number of the element equals the number of protons.

Answer:

Which of the following best describes the make up of Saturn's rings?(1 point) solid bands of sand and dust that formed from the start of the universe solid bands of sand and dust that formed from the start of the universe material from comets that have passed through Saturn's atmosphere material from comets that have passed through Saturn's atmosphere dust, rock, and ice particles that orbit due to Saturn's gravity dust, rock, and ice particles that orbit due to Saturn's gravity debris and rocks from other planets that orbit around Saturn

The make up of Saturn's ring are dust, rock, and ice particles that orbit due to Saturn's gravity"

Saturn is one of the 9 planets of the solar system. It is considered to be the second largest planet.

Saturn has seven large rings orbiting around it. These rings are believed to be pieces of comets, asteroids, or shattered moons that broke up before they reached the planet. And this shattered comets or asteroid are believed to be torn apart by Saturn's powerful gravity.

These comets or asteroids are made of billions of small chunks of ice and rocks which are covered or coated with other small materials such as dust particles.

Thus, the correct option that matches the above explanation is "dust, rock, and ice particles that orbit due to Saturn's gravity"

Learn more here: https://brainly.com/question/24569357

Answer:

yes it is true they apply necessary safety measures

Answer: Label the test tubes, wear chemical protective gloves, tie long hair back

Explanation:

Just got it wrong

Answer:

d

Explanation:

solids the modicual are tightly packed

liquid, more room to move around  aka not so tightly packed

gas, can move where ever it wants  aka not paked at all

Explanation:

Force=mass *acceleration

F=300*5

f

F=1500N

Answer:

167.86 tonnes

Explanation:.

I am assuming the iron oxide is Fe2O3 (Haematite) which is the most common form of iron oxide.

From the atomic masses:

Maximum Mass of iron = 240 *  2*55.845 / (2*55.845 + 3*15.999))

= 240 * 111.69 / (159.687)

= 167.86 tonnes

Answer:

By definition, a pure substance or a homogeneous mixture consists of a single phase. A heterogeneous mixture consists of two or more phases. When oil and water are combined, they do not mix evenly, but instead form two separate layers. Each of the layers is called a phase.

Explanation:

Answer:

what is the question????

Answer

 I think a helicopter would be fastest, just sayin.

Explanation:

Answer:

2.53 kilometers

Answer:

54.883, so rougly about 54.9 liters.

Explanation:

To convert gallons to liters, multiply the amount of gallons by 3.785.

14.5 * 3.785 = 54.883

Taking into account the change of units, the size of the tank is 54.88 liters.

In first place, the rule of three is a tool used to quickly solve problems involving a proportional relationship between two variables.

The rule of three is a way of solving problems of proportionality between three known values and an unknown value, establishing a relationship of proportionality between all of them.

If the relationship between the magnitudes is direct, that is, when one magnitude increases, so does the other (or when one magnitude decreases, so does the other), the direct rule of three should be applied.

The rule of three is applied as follows, with A, B and C being known values ​​and D being an unknown value: if A maintains a certain relationship with B, and it is known that C and D have the same relationship, it is possible to calculate the unknown value D using the following expression:

[tex]D=\frac{CxB}{A}[/tex]

In this case, the rule of three can be applied as follows: if 1 gallon is equal to 3.785 liters, 14.5 gallons are equal to how many liters?

[tex]D=\frac{14.5 gallonsx3.785 liters}{1 gallon}[/tex]

Solving:

D= 54.88 liters

In summary, the size of the tank is 54.88 liters.

Learn more with this example:

Answer:

150 mL of 1.50 M HCL

Explanation:

So the equation you need to solve this equation is:

M1*V1=M2*V2 --> M1= Molarity of the acid you are diluting V1= Volume of the solution you need to dilute. M2=The molarity of thee solution you have made. V2=Volume of the solution you have made

M1= 1.50 M HCL

V1= Unknown

M2=0.450 M HCL

V2= 500 mL

Simple algebra says that V1= (1.5*500)/.450 = 150 mL of 1.50 M HCL

Answer:

0.44mol

Explanation:

1mol/102g=xmol/45.1g

-> x=(45.1x1)/102

x=0.44mol

Fluoridation is the process of adding fluorine to drinking water to avoid tooth decay.

The question is incomplete; the complete question is;

Fluoridation is the process of adding fluorine compounds to drinking water to help fight tooth decay. A concentration of 1 ppm of fluorine is sufficient for the purpose. (1 ppm means one part per million, or 1 g of fluorine per 1 million g of water.) The compound normally chosen for fluoridation is sodium fluoride, which is also added to some toothpastes. Calculate the quantity of sodium fluoride in kilograms needed per year for a city of 50,000 people if the daily consumption of water per person is 150 gallons.

(Sodium fluoride is 45.0 percent fluorine by mass. 1 gallon = 3.79 L; 1 year = 365 days; 1 ton = 2000 lb; I lb = 453.6 g; density of water = 1.0 g/mL.)

The quantity of sodium fluoride in kilograms needed per year for a city of 50,000 people if the daily consumption of water per person is 150 gallons is [tex]9.32 * 10^9 Kg[/tex].

From the question, we know that;

Daily consumption of water per person = 150 gallons.

Population of the city = 100,000 people

Total daily city consumption =[tex]100,000 *  150 gallons = 15 * 10^6 gallons[/tex]

Annual water consumption = [tex]15 * 10^6 gallons * 365 = 5.475 * 10^9 gallons[/tex]

1 gallon = 3.785 L = 3.785 kg

[tex]5.475 * 10^9 gallons = 5.475 * 10^9 gallons * 3.785 kg/ 1 gallon = 2.1 * 10^10 Kg[/tex]

Since sodium fluoride accounts for 45% by mass of water

Mass of sodium fluoride= [tex]0.45 * 2.1 * 10^10 Kg= 9.32 * 10^9 Kg[/tex]

Learn more; https://brainly.com/question/14805580

Explanation:

The extract of plant is not done in fixed proportion

it is heterogeneous

Answer:

c

Explanation:

took test on usa testprep

When gas in a discharge tube is excited to higher energy level after some seconds they return to the ground level by releasing energy in the form of light. Thus energy jumps by electron due to excitation is correct option.

A gas discharge tube is an electronic devise containing inert gases that ionizes and conducts results in  emission of light.

When a potential  is applied between the electrodes in a gas discharge tube, and the pressure is reduced, the gas particles inside forms a plasma of ions.

The electrons released when excited to higher energy level by absorbing energy and returns to the initial state by emitting energy in the form of light, the discharge tube glows.

The color emitted by the discharge tube vary based on the gas in the tube. Each type of gaseous ions emit different colors.

Therefore, the light emission in gas discharge tube is due to energy hike during electron excitation and then relaxing by emitting the light energy. Thus, option c is correct.

To find more about gas-discharge tube, refer the link below:

https://brainly.com/question/5468708

#SPJ2

Answer:

zxcdfzdg

Explanation:

zszghzd

Answer: Three liquids that could fill a bowl with clear liquid in your kitchen could be alcohol, dish soap, juice (without pectin or pulp), sports drinks, and water (carbonated, coconut, flavored, or plain).