35
Select the correct answer.
Which is true according to the law of conservation of energy?
A.
In a closed system, the total amount of energy in the universe keeps on changing.
B.
The supply of energy is limited, so it is essential to conserve it.
C.
In a closed system, energy can be created and destroyed.
D.
In a closed system, energy cannot be used faster than it is created.
E.
In a closed system, the total energy always remains constant.

Answers

Answer 1

Answer:

its a

Explanation:


Related Questions

What is the mass of 34.6 L of oxygen? How many molecules of oxygen are in 34.6 L of oxygen?

Answers

Answer:

49.4 grams; 9.29 x 10^23 molecules O2

Explanation:

In order to solve for the mass of oxygen, you first must find out how many moles of oxygen there are in 34.6 L.

There are 22.4 L in one mole of gas, so to get amount of moles, divide 34.6 by 22.4.

34.6 / 22.4 = 1.544 mol

In order to calculate mass, multiply the amount of moles by the molar mass of oxygen, which is in this case 32.00 g/mol.

1.544 * 32.00 = 49.4 grams

To calculate the amount of molecules, multiply the amount of moles by Avogadro's number, 6.02 x 10^23, which basically represents how many atoms/molecules there are in a mole of any substance.

1.544 * (6.02 x 10^23) = 9.29 x 10^23 molecules O2

What is the pH of 0.0030 M NaOH

Answers

Answer:The pH of 0.0030 is 12.7.

Explanation:NaOH is a very storng base that it is dissociate.

Answer:

The pH is about 12.7.

Explanation:

Please help i forgot how to do this

Answers

Answer:

2 significant figures

Explanation:

0.19312

0.19 or 0.2

The answer is 0.19312

Hope this helped! If it does then I would appreciate it if you marked me brainliest. Have a nice day

what has changed in the atmosphere that give the rock strata the appearance of rust?(red/orange color).

Answers

Answer:

Explained below.

Explanation:

What has changed in the atmosphere is that oxidation has occurred where an oxidizing chemical specie has reacted with an oxygen containing compound.

Now these chemicals when they react with rain and fall on rocks react with the rocks to weaken them in a process known as chemical weathering.

Now when this weathering from the oxidizing chemicals from the rain react with rocks that contain iron, it leads to the rock having an appearance of rust.

A gas has a volume of 465. mL at 725 mmHg of pressure. What
will be the pressure if the volume increases to 841 mL?

Answers

Answer:688

Explanation:

In a neutral solution, the concentration of H+ is
Group of answer choices

Answers

Answer:

equal to [OH-]

Hydrogen ion concentration is more conveniently expressed as pH, which is the logarithm of the reciprocal of the hydrogen ion concentration in gram moles per liter. Thus, in a neutral solution the hydrogen ion (H+) and the hydroxyl ion (OH−)

16) What is the acceleration of an object with a mass of 31.5 kg when an unbalanced force
of 223 N is applied to it?

Answers

Answer:

a= 7.07 m/s^2

Explanation:

Newton's second law of motion states that the acceleration of an object is produced by the net force.

the formula to calculate the force: F=ma

you just rearrange it to solve for a

a= F/m a=223/31.5

=7.07

Which is true for a substance that releases energy?
OA. The energy release decreases the molecular motion and the kinetic energy of the substance.
B. The energy release decreases the molecular motion but increases the kinetic energy of the substance.
C. The energy release increases the molecular motion and the kinetic energy of the substance.
D. The energy release increases the molecular motion but decreases the kinetic energy of the substance.
E. The energy release is used only to change the state of the substance.

Answers

I’m not sure but I think it’s the first one

Answer the question in image attached

Thanks!

Answers

Answer: i think the 3,4,2

Explanation:

Answer:

i think its 2, 3 and 4

ionic and molecular compounds, polyatomic ions, ch chemical equations

I have a flask filled with water and on top a stopper .

I heat it over a flame .

after some time what will happen to the stopper

Answers

Answer:

A vacuum flask (also known as a Dewar flask, Dewar bottle or thermos) is an insulating storage vessel that greatly lengthens the time over which its contents remain hotter or cooler than the flask's surroundings. Invented by Sir James Dewar in 1892, the vacuum flask consists of two flasks, placed one within the other and joined at the neck. The gap between the two flasks is partially evacuated of air, creating a near-vacuum which significantly reduces heat transfer by conduction or convection.

The typical design of a Thermos brand vacuum flask, used for maintaining the temperature of fluids such as coffee.

Laboratory Dewar flask, Deutsches Museum, Munich

Diagram of a vacuum flask

A cryogenic storage dewar of liquid nitrogen, used to supply a cryogenic freezer

Vacuum flasks are used domestically, to keep beverages hot or cold for extended periods of time, and for many purposes in industry.

pls make me as brainliest

When patterns of stars appear to move across the sky, it provides evidence that ________.

A. Earth and stars move together
B. Earth rotates in space
C. patterns of stars can change
D. stars actually move

Answers

Answer:

Answered B

Explanation:

The earth moves which makes the stars and everything in space seem like its moving

What moon phase happens 2 weeks after this moon phase?
First Quarter
O Full Moon
Last Quarter
New Moon

Answers

I think it’s the last quarter

Calculate the decrease in temperature when 7.00 L at 21.5 °C is compressed to 4.00 L. The pressure remains constant at 101.3 kPa.

Answers

Explanation:

[tex] \frac{P _{1} V _{1} }{T _{2}} = \frac{P _{2} V _{2}}{T _{1}} \\ \frac{(101300 \times 7)}{(21.5 + 273)} = \frac{(101300 \times 4)}{T _{2}} \\ T _{2} = \frac{(405200 \times 294.5)}{(709100)} \\ T _{2} = 168.3 \: kelvin \\ decrease \: in \: temperature = (294.5 - 168.3) \\ = 126.2 \: kelvin[/tex]

When 3.20 moles of magnesium is heated and placed in a container of nitrogen gas the two substances undergo a synthesis reaction. How many moles of nitrogen gas will react? 3 Mg (s) + 1 N2 (g) → 1 Mg3N2 (s)

Answers

Answer:

1.06 moles of nitrogen gas will react with 3.20 moles of magnesium in the container.

Explanation:

[tex]3 Mg (s) + 1 N_2 (g) \rightarrow 1 Mg_3N_2 (s)[/tex]

Moles of magnesium heated = 3.20 mol

According to reaction, 3 moles of magnesium reacts with 1 mole of nitrogen gas, then 3.20 moles of magnesium will react with:

[tex]=\frac{1}{3}\times 3.20 mol=1.07 \text{ mol of }N_2[/tex]

1.06 moles of nitrogen gas will react with 3.20 moles of magnesium in the container.

Two beakers each contain 200 mL of water. Into one beaker, a student adds 5.0 g NaI. Into the other, she adds 5.0 g of KI. What is the expected effect on the boiling points of the solutions?A) the NaI solution will have a higher boiling point than the KI solutionB) the KI solution will have a higher boiling point than the NaI solutionC) the boiling points of both solutions will be elevated to the same temperature, above 100 degrees CelsiusD) the boiling points of both solutions will remain at 100 degrees Celsius

Answers

Answer:

A) the NaI solution will have a higher boiling point than the KI solution

Explanation:

We must have it behind our minds that the addition of a solute to water elevates the boiling point of water.

Boiling point elevation is a colligative property. It depends on the amount of solute present.

We know that;

ΔTb = Kb m i

Where;

ΔTb = boiling point elevation

Kb = boiling point constant

m = molality

i = Van't Hoff factor

Since KI and NaI has the same number of particles(two particles each), the boiling point elevation (ΔTb) depends on the molality of each solution. The molality also depends on the molar mass of each substance. The molality of NaI is greater than the molality of KI hence the boiling point NaI is greater than the boiling point of KI.

So;

200mL of water = 200g of water

Mass of solvent = 200g/1000 = 0.2 Kg

Molality of NaI = 5g/150 g/mol * 1/0.2 = 0.167 m

molality of KI = 5g/166 * 1/0.2 = 0.151 m

Kb for water = 0.512 oC m-1

Boiling point of water = 100 oC

Let the boiling point of NaI be A

A - 100 = 0.512 *  0.167  * 2

A = (0.512 *  0.167  * 2) + 100

A = 100.171 oC

Let the boiling point of KI be B

B - 100 = 0.512 * 0.151  *  2

B = (0.512 * 0.151  *  2) + 100

B = 100.154 oC

Hence;

Boiling point of NaI > Boiling point of KI

Of the following which atom pairs will form covalent bonds

Answers

Answer:

si and p

o and F

Explanation:

covalent bonds are formed between non metals

1 cannot be accepted as Na is a metal

3 cannot be accepted as Ca is a metal

5 cannot be accepted as Mg is a metal

Which statement about hydrocarbons is FALSE?
a
The number one use of hydrocarbons is as a fuel
source.
b
Most hydrocarbons we use today come from
sustainable, renewable sources.
с
Hydrocarbons are useful in industries from
transportation to road work to cosmetics.
d
The bulk of hydrocarbons we use today were
formed hundreds of millions of years ago.

Answers

Answer:

b

Explanation:

Hydrocarbons provide 84% of the world's energy, but they are non-renewable. Hydrocarbons are the most economic form of energy.

Name the planet: Until recently, this stormy, blue-colored planet had a great dark spot on it, which was a high pressure cyclone.

Answers

It’s Neptune hehe :))

Answer:

Explanation:

THE PLANET NAME IS NEPTUNE

Tides are the rise and fall of surface levels of Earth's ocean water caused by the gravitational effects of which two celestial objects?
A)stars and planets
B)comets and meteors
C)earthquakes and volcanoes
D)moon and sun

Answers

Answer:

D)Moon and sun

Explanation:

Because the gravitational pull of the moon is weaker on the far side of the Earth, inertia wins, the ocean bulges out and high tide occurs.

hope it helps:)

D) Moon and sun causes the rise and fall of tides

_S8+_O2=_SO2
please help balance

Answers

Answer:

S8+8o2 = 8so2

this is balance d

So3+H2o→H2 So4
identify the nature of this reaction
helpp please i'm such a failure​

Answers

THE REACTION IS COMBINATION REACTION!

Juan Carlos placed 35 grams of ice into a dry, 200-gram container. The top
of the container was attached tightly. When the ice was completely melted, the
student measured the mass of the container with the liquid water. What should the
mass of the liquid water in the container be?
A. 35 grams
B. 165 grams
C. 200 grams
D. 235 grams

Answers

Mass of the liquid water in the container is 35 grams-

Mass doesn't depends upon the state of compounds.

The mass of the liquid water in the container should be 35 grams.

Mass would not change during a change of state because the number of particles does not change during a state change. It does not matter if a substances freezes, boils, melts, sublimates.

So, the mass of liquid water in the container is the same as ice. Hence, the correct option is (A).

To know more about:-

brainly.com/question/11810264


What is the major difference, in terms of weathering type, between Albany, NY and Washington, D.C.? What might explain this difference?

Answers

Base your answers to the following questions on the graph below, which shows the effect that average yearly precipitation and temperature have on the type of weathering that will occur in a particular region.

City
Avg. Yearly Temp (oC)
Avg. Yearly Precip (cm)
Albany, NY
9oC
98 cm
Washington, D.C.
15oC
111 cm
Phoenix, AZ
20oC
22 cm

The breakdown or dissolution of rocks and minerals of the planet's surface is called weathering it can be chemical, biological or physical.

Chemical weathering occurs in regions with high rainfall and high temperature.

In Albany, NY the temperature is 9°C with 98 cm rainfall while in Washington, DC the temperature is 15°C with 111 cm rainfall that is Washington is hotter compared to Albany so it will have chemical weathering.

Water (rainfall) and temperature is the main cause of weathering as they loosen and breaks the mineral of rock surfaces.

The rocks and minerals get dissolved in the water bodies because of erosion by which they get carried in oceans.

Therefore, Albany will have mechanical while Washington will suffer from chemical weathering.

To learn more about weathering types follow the link:

https://brainly.com/question/516958

What happens to a catalyst used in a reaction?
O A. It is unchanged by the reaction.
OB. It is bonded to the products.
O c. It is broken up by the reactants.
O D. It is used up in the reaction.
help asap very appreciated

Answers

A catalyst used in a reaction remains unchanged

In sexual reproduction, if each chromosome in a pair has the same genes, how is genetic variety possible?

Answers

Answer:

The same genes or slightly different versions of the same gene can be found on each chromosome in a pair. They form a line and split off bits of themselves, which they barter with one another. In sexual reproduction, crossing over is the first method that genes are shuffled to develop genetic variation.

Which of the following elements has the lowest electron affinity?

a. Si
b. F
c. Cl
d. K

Answers

Answer:

k

Explanation:

electron affinity (EA) depends on various factors like effective nuclear charge (enc) , size of the atom, ellipticity of sub-shell (ep) , nature of configuration.

more is the enc more will be the EA

more is the size less will be the EA

more valance shell ellipticity (closer to the nuclei) more will the EA ( all given element posses P orbital in the valance shell)

The answer is K I just took the test

Water flows more easily than syrup, which means water has

A. higher viscosity than syrup

B. lower viscosity than syrup

C. equal viscosity to syrup

Answers

Answer:

lower viscosity than syrup

Answer:

higher viscosity than syrup flows more easily than syrup.

Please give me Brainliest answer

-Carbon and Oxygen combine to from carbon dioxide

Answers

Answer:

Carbon and oxygen combine to form two oxides, carbon monoxide and carbon dioxide in which the ratio of the weights of carbon and oxygen is respectively 12:16 and 12:32.

The mixture of carbon and oxygen is called carbon dioxide

Please help no links

Ms. Daly had Hydrogen gas that was cooled from 100 °C to 50.5°C. The new volume was 20 L. What was its original volume?
20.
50.

Answers

Answer:

23 L

Explanation:

We'll begin by converting celsius temperature to Kelvin temperature. This can be obtained as follow:

T(K) = T(°C) + 273

Initial temperature (T₁) = 100 °C

Initial temperature (T₁) = 100 °C + 273

Initial temperature (T₁) = 373 K

Final temperature (T₂) = 50.5 °C

Final temperature (T₂) = 50.5 °C + 273

Final temperature (T₂) = 323.5 K

Finally, we shall determine the initial volume of gas. This can be obtained as follow:

Initial temperature (T₁) = 373 K

Final temperature (T₂) = 323.5 K

Final volume (V₂) = 20 L

Initial volume (V₁) =?

V₁/T₁ = V₂/T₂

V₁ / 373 = 20 / 323.5

Cross multiply

V₁ × 323.5 = 373 × 20

V₁ × 323.5 = 7460

Divide both side by 323.5

V₁ = 7460 / 323.5

V₁ = 23 L

Thus, the original volume of the gas is 23 L

A) 400 gramos de disolución al 6 % m/m. R: 24 g sto. Y 376 g ste. b) 56 gramos de disolución al 30 % m/m. R: 16,8 g y 39,2 g c) 450 gramos de disolución al 10 % m/m R: 45 g y 405 g d) 200 gramos de disolución al 5 % m/m R: 10 g y 190 g e) 450 gramos de disolución al 20 % v/v R: 90 mL y 360 mL f) 980 mL de disolución al 25 % v/v R: 245 mL y 735 mL. g) 50 mL de disolución al 30 % v/v R: 15 mL y 35 Ml

Answers

Answer:

A) 24g soluto y 376g solvente.

B) 16.8g soluto y 39.2g solvente

C) 45g soluto y 405g solvente

D) 10g soluto y 190g solvente

E) 90mL soluto y 360mL solvente

F) 245mL soluto y 735mL solvente

G) 15mL soluto y 35mL solvente

Explanation:

El porcentaje masa/masa (% m/m) se define como la masa de soluto presente en 100g de solución (Soluto + solvente).

De la misma manera, el porcentaje volumen/volumen se define como el volumen de soluto en 100mL de solución:

A) 400 gramos de disolución al 6 % m/m.

400g solución * (6g soluto / 100g solución) = 24g soluto

400g solución - 24g soluto = 376g solvente

b) 56 gramos de disolución al 30 % m/m.

56 gramos de disolución al 30% m/m.

56g solución * (30g soluto / 100g solución) = 16.8g soluto

56g solución - 16.8g soluto = 39.2g solvente

c) 450 gramos de disolución al 10 % m/m

450 gramos de disolución al 10% m/m.

450g solución * (10g soluto / 100g solución) = 45g soluto

450g solución - 45g soluto = 405g solvente

d) 200 gramos de disolución al 5 % m/m

200 gramos de disolución al 5% m/m.

200g solución * (5g soluto / 100g solución) = 10g soluto

200g solución - 10g soluto = 190g solvente

e) 450 mL de disolución al 20 % v/v

450 mL de disolución al 20% m/m.

450 mL * (20mL soluto / 100mL solución) = 90mL soluto

450mL solución - 90mL soluto = 360mL solvente

f) 980 mL de disolución al 25 % v/v

980 mL de disolución al 25% m/m.

980 mL * (25mL soluto / 100mL solución) = 245mL soluto

980mL solución - 245mL soluto = 735mL solvente

g) 50 mL de disolución al 30 % v/v

50 mL de disolución al 30% m/m.

50 mL * (30mL soluto / 100mL solución) = 15mL soluto

50mL solución - 15mL soluto = 35mL solvente

Other Questions
Please answer it. I will give brainliest if its correct.. Write one paragraph (5 sentences) on the role geography and climate played in promoting the development of different types of work or economic activity for human survival and gain such as New England farming, Middle Atlantic farming and Southern farming during the 1600s and 1700s as a part of people getting responsible for their lives. Read the sentence from the passage.Rather than allowing developers to tear down old buildings simply to put up new ones, local governments could enact ordinances to preserve their area's architecture.Why is this sentence important to the passage as a whole?A. It concludes the writer's discussion of modern architecture.B. It summarizes the writer's attitude toward government involvement in architecture.C. It begins to introduce solutions to the problems the writer raises.D. It begins to describe the problems the writer wants to highlight. How Zero feels about not being able to read.The movie holes Please help me! Write a research-based argumentative essay for or against health care for everyone.i need this finished by tomorrow!!!!! please help Brand A green beans costs $7.00 for a 16 ounce pack and Brand B green beans costs $9.00 for a 20 ounce pack.a. Which brand of green beans has the lowest price per ounce?b. Explain your reasoning. Be specific (include the price per ounce for each brand in your explanation). Which of these values for p and a will cause the function f(x)=Pax to be an exponential growth function ___ broke into two states because its citizens could not agree on which side to joina. north carolina b. arkansas c. tennessee d. virginia which of the following government is less likely to protect freedom of speech and freedom of the press What is the solution to the equation log2 (3x 4) = 5? !!!!!help will mark brainliest!!!!!In case of a kidnapping, when state boundaries are crossed, the offender would be tried in which court?A. County court B. State court C. Federal court D. County court help me!!!!!!!!!plzzz "Features like these have never been seen on comets," Chief Project Scientist, Dr. BrownleecommentedWhich text feature, if added to the passage, would best clarify the idea that the Wild 2 is differentfrom most other comets?A a table summarizing the key features of Wild 2Ba diagram with labels explaining the structure of Wild 2a timesAnmarizing the major discoveries made about Halley's cometDa photograph of Wild 2 and a photograph of Halley's comet placed side by side HELP PLZ THIS IS DUE ON MONDAY!!!! What Pericles did that angered the aristocracy?? Given: x + 3.8 > -10.02.Choose the solution set. 3 Select the correct answer. Which measure of center is the most appropriate for this data set? 20, 6, 42, 13, 15, 10, 9, 12, 12 A meanB medianC modeD mean absolutely median y=x+5please help me with this problem I'm really struggling to answer the question. According to the article, why do people gomovies in droves? the sum of 2 numbers is 65 and the difference is 7 What is the measurement of B ?