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Answer:

A, D, E

Explanation:

a. "A dog panting to stay cool on a hot day" is a mechanism the dog employs to maintain it's body temperature. This is homeostasis.

d. "A bear hibernates in order to reduce their metabolism and conserve energy during the winter" is also all about keeping the internal condition of the bear's body constant. So this is also an example of homeostasis.

e. The lizard trying to keep regulate it's body temperature is also part of homeostasis.

Answer:

[tex]^{31}_{15}P[/tex] is the isotopic notation of the atom

Explanation:

The isotope notation is:

[tex]^a_bX[/tex]

Where a is the mass number = Number of protons + Number of neutrons

b is atomic number = Number of protons

The atomic number define the nature of the atom, the element with atomic number = 15 is phosphorus, P:

[tex]^a_bP[/tex]

a = 15 protons + 16 neutrons = 31

b = 15

[tex]^{31}_{15}P[/tex] is the isotopic notation of the atom.

Answer:

Mass = 8.5 g

Explanation:

Given data:

Mass of ammonia = ?

Number of moles = 0.5 mol

Solution:

Formula:

Mass = number of moles × molar mass

Molar mass of ammonia = 17 g/mol

By putting values,

Mass = 0.5 mol × 17 g/mol

Mass = 8.5 g

Answer:

Love is not only the thing in this world!

Study hard, you can choose a better way of life.

Answer: lighter atoms

energy

neutrons

Explanation:

A nuclear fission is simply defined as a nuclear reaction whereby the nucleus of an atom is being divided into smaller nuclei which are also lighter. An energy is also released when this occurs.

Therefore, the products of a fission include lighter atoms, energy and neutrons.

Answer:

lighter atoms

energy

neutrons

Explanation: took test

Answer:

Find alternatives to fossil fuels

Explanation:

The most effective long - term solution to reduce the amount of carbon dioxide emission is to find alternatives to fossil fuels.

Fossil fuels consumption and use in most industrial processes are some of the leading causes of huge carbon signatures in the atmosphere.

C₆H₁₂O₆ has the greatest molar mass (180 g/mol)

Given

Compounds of A. H2O B. C6H12O6 C. HNO3 D. C2H6

Required

The greatest molar mass

Solution

The molar mass(molecular mass-formula mass) of a compound is the sum of the relative atomic mass (Ar) of the constituent elements of the compound

A. H₂O : 2.1+16 = 18 g/mol

B. C₆H₁₂O₆ : 6.12+12.1+6.16=180 g/mol

C. HNO₃ : 1.1+1.14+3.16=63 g/mol

D. C₂H₆ : 2.12+6.1 = 30 g/mol

Answer: With the cold front, warm air is rapidly forced upward (like the shavings) in advance of the actual front (the “cutter”), creating towering cumulus clouds, some hard showers and quite possibly a few gusty thunderstorms followed by a push of cooler and drier air in its wake.

Explanation:

Answer: Entropy.

Explanation:

If we recall the laws of thermodynamics, there is a state function called entropy, that is related to the disorder in the system.

Such that, for example, in a gas expansion, we will have an increase in the "disorder" then we will have an increase in the entropy, this happens because we have more volume where the particles can be, then we have a larger number of "microstates" (or microscopic states, which refers to the states of the particles that conform the gas)

Particularly, when we go into statistical thermodynamics, there is something called the "Statistical entropy" that is related to the information theory, where the entropy depends on the number of possible outcomes that some event, like a chemical reaction, can have.

For a larger number of possible outcomes, we will have a larger entropy (we can think of this larger number of possible options as a disorder) and this entropy will be related to the statistical probability of each one of those outcomes.

Where the (most general) equation for the entropy is:

S = Kb*Σpₙ*ln(pₙ)

Where pₙ is the probability for the n-th outcome.

Kb is Boltzman's constant.

Answer:

The new class of compound formed is an alcohol.

Explanation:

The treatment of an alkene with Hg(OAc)₂ in alcohol followed by reaction with NaBH₄ gives an alcohol. This reaction is known as oxymercuration-demercuration reaction. It is a two-step pathway which proceeds in the Markovnikov manner. In this reaction, the alkene react with the Mercury salt (Hg(OAc)₂) and a nucleophile (alcohol) to form an organomercury intermediate. The intermediate's carbon-mercury bond is then converted to carbon-hydrogen bond by the reaction with NaBH₄. An alcohol is then produced.

Answer: the destruction of the butterflies’ environment

Explanation:

A mutation that would result in darker wings will mean that the birds that prey on them will stop eating a lot of them so this won't lead to extinction.

A decrease in the birds that eat the butterflies will also mean that the butterflies will survive more because they will have less predators.

Overproduction of butterfly offspring means more butterflies so they will not go extinct.

If their habitat was destroyed however, the butterflies might find it hard to survive as any new environment they go to might not be suitable leading to their extinction.

Answer:

I believe it is c

Explanation:

Answer:

Explanation:

The density of a substance can be found by using the formula

[tex]density = \frac{mass}{volume} \\[/tex]

volume = final volume of water - initial volume of water

volume = 260.5 - 242 = 18.5 mL

We have

[tex]density = \frac{194.3}{18.5} \\ = 10.5027[/tex]

We have the final answer as

Hope this helps you

Answer:

12.01% by mass

Explanation:

Percent by mass is 100 times the mass of solute (ammonia) over the mass of the solution. In molarity, we have the moles of ammonia per liter of solution. There are 6.70moles of NH3 in 1L. Thus, we need to convert the moles of ammonia to grams and the liters of solution to grams:

Mass ammonia - Molar mass: 17.031g/mol-

6.70moles * (17.031g / mol) = 114.1g NH₃

Mass solution:

1L * (1000mL / 1L) = 1000mL * (0.950g/mL) = 950g

Percent by mass:

114.1g NH₃ / 950g * 100 =

Answer:

See explanation

Explanation:

Chlorine has three shells. We know that the first shell contains two electrons, the other shell has eight electrons while the last shell has seven electrons. This means that chlorine has seventeen electrons.

For sodium, there are also three shells. The first shell has two electrons as usual. The next shell has eight electrons while the last shell has only one electron. This makes a total of eleven electrons for sodium.

Answer: sodium-11

chlorine-17

Explanation: meow

Answer:

Environmental Changes

Explanation:

Answer:

d

Explanation:

Answer:

the first one

Explanation:

Answer:

The volume that the same gas will occupy at 101.3 kPa if the temperature is kept constant is 5.27 L.

Explanation:

As the volume increases, the particles (atoms or molecules) of the gas take longer to reach the walls of the container and therefore collide with them less times per unit of time. This means that the pressure will be lower because it represents the frequency of collisions of the gas against the walls. In this way pressure and volume are related, determining Boyle's law that says:

"The volume occupied by a given gaseous mass at constant temperature is inversely proportional to pressure"

Boyle's law is expressed mathematically as:

P * V = k

Now it is possible to assume that you have a certain volume of gas V1 that is at a pressure P1 at the beginning of the experiment. If you vary the volume of gas to a new value V2, then the pressure will change to P2, and it will be fulfilled:

P1 * V1 = P2 * V2

In this case, you have:

Replacing:

92 kPa* 5.80 L= 101.3 kPa* V2

and solving, you get:

[tex]V2=\frac{92 kPa* 5.80 L}{101.3 kPa}[/tex]

V2= 5.27 L

The volume that the same gas will occupy at 101.3 kPa if the temperature is kept constant is 5.27 L.

Answer:

The correct answer choices are B and D.

Explanation:

A volcanic eruption happens when magma reaches the surface of the earth.  Depending on the amount of gas and the silica content of the magma, the lava and the type of eruption can vary.  Silica, which forms from the elements silicon and oxygen, makes the lava thicker and less runny. When lava is thick, the volcanic eruption tends to be more explosive.  The amount of silica also changes the color and density of the lava, which then makes different kinds of igneous rocks.  As the gas content of the lava goes up, the eruption becomes more explosive.  

Answer:

the first one

Explanation:

Answer:

 .24 mg

Explanation:

The mineral contains .016 % silicon

mass of the mineral = 1.5 kg

mass of silicon = 1.5 x .016 %

= 1.5 x .016 / 100

= 24 x 10⁻⁵ kg

= 24 x 10⁻² mg

= .24 mg .

Answer:

pH = 12.22

Explanation:

... To make up 170mL of solution... The temperature is 25°C...

The dissolution of Barium Hydroxide, Ba(OH)₂ occurs as follows:

Ba(OH)₂ ⇄ Ba²⁺(aq) + 2OH⁻(aq)

Where 1 mole of barium hydroxide produce 2 moles of hydroxide ion.

To solve this question we need to convert mass of the hydroxide to moles with its molar mass. Twice these moles are moles of hydroxide ion (Based on the chemical equation). With moles of OH⁻ and the volume we can find [OH⁻] and [H⁺] using Kw. As pH = -log[H⁺], we can solve this problem:

Moles Ba(OH)₂ molar mass: 171.34g/mol

0.240g * (1mol / 171.34g) = 1.4x10⁻³ moles * 2 =

2.80x10⁻³ moles of OH⁻

Molarity [OH⁻] and [H⁺]

2.80x10⁻³ moles of OH⁻ / 0.170L = 0.01648M

As Kw at 25°C is 1x10⁻¹⁴:

Kw = 1x10⁻¹⁴ = [OH⁻] [H⁺]

[H⁺] = Kw / [OH⁻] = 1x10⁻¹⁴/0.01648M = 6.068x10⁻¹³M

pH:

pH = -log [H⁺]

pH = -log [6.068x10⁻¹³M]

Answer:

A

Explanation:

My reason is color change is an example

Mixing reactants is a chemical change clue

formation of precipitate is a clue

so that leaves A

Answer: 55.56 moles of MgO

Explanation:

1 mole = avogadro number

if 6.21x10^25 atoms then molecules of MgO (equal numbers of Mg and O atoms)

= 0.5*6.21x10^25 = 3.105 molecules of MgO

So moles of MgO = 0.5*6.21*10^25/avogadro number = 55.56

1x+cb=23

thios  is right because math

Answer:

57.6 KJ/mol

Explanation:

We have that;

T1 = 301 K

T2= 311 K

k1 = k1

k2= 2k1

R = 8.314 JK-1

Ea= ?

So;

ln(k1/k2) = (-Ea/R) (1/T1 - 1/T2)

ln (k1/2k1) = -(Ea/8.314) (1/301 - 1/311)

ln(1/2) = -(Ea/8.314) (3.3 * 10^-3 - 3.2 * 10^-3)

-0.693 = -(Ea/8.314) 0.1 * 10^-3

-0.693/ 0.1  * 10^-3 = -(Ea/8.314)

-6930 =  -(Ea/8.314)

Ea = 6930 * 8.314

Ea = 57.6 KJ/mol

Answer:148.31 Grams per mol

Explanation: It has been a long time since I took chemistry.

I believe you add up all the elements molar mass.

magnesium nitrate is Mg(NO3)2 so you add

MG  24.30

N 14.01 * 2 = 28.01

O 16.00 * 6 = 96.00

total is 148.31 grams per mol

I hope this helps.  

The molar mass of magnesium nitrate is 148.31 grams per mol.

The term molar mass is defined as the ratio between the mass and the amount of substance of any sample of the known compound. A mole of any substance is 6.022 × 10²³ molecules.

1 mole = 6.022 × 10²³ elementary entities.

The molar mass of a substance is calculated by adding the quality atomic masses in g/mol of the constituent atoms. Molar mass is represented by the symbol "M".

For calculating molar mass of magnesium nitrate is Mg(NO3)2

Mg =  24.30

Nitrogen = 14.01 × 2

= 28.01

Oxygen = 16.00 × 6

= 96.00

Therefore, molar mass of magnesium nitrate is Mg(NO3)2

=  24.30 + 28.01 + 96.00

=  148.31 grams per mol.

Thus, The molar mass of magnesium nitrate is 148.31 grams per mol.

To learn more about the molar mass, follow the link;

https://brainly.com/question/12127540

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