A. C5H14
B. C5H12
C. C6H14
D. C6H12

The mass of He gas = 21.428 g

Given

120 liters of He gas​

Required

the mass in grams

Solution

Conditions at T 0 ° C and P 1 atm are stated by STP (Standard Temperature and Pressure). At STP, Vm is 22.4 liters/mol.

Mol for 120 L :

[tex]\tt \dfrac{120}{22.4}=5.357~moles[/tex]

Mass of He gas(MW=4 g/mol) :

[tex]\tt mass=mol\times Ar\\\\mass=5.357\times 4=21.428~g[/tex]

Answer:

1. Pollution caused the bark to become darker.

2. The light-colored peppered moth had a higher chance of survival

3. The dark-colored peppered moth had a higher chance of survival

4. During the Industrial Revolution, the barks of trees got darks, causing the moths to be seen easily on a dark background. Now predators were more likely to eat the lighter cloured moths as they were easier to find. Since fewer light-colored moths were surviving, there was a smaller likelihood of light moths surviving long enough to reproduce. Since there were fewer light-colored moths, the dark-colored moths had less competition and were able to reproduce quickly.

5. Sunny, warm place: I live in a place with lots of light and sunshine, so it would be easier for light moths to blend in with their environment long enough to reproduce and thrive.

Dark, rainy Place: I live in a place with little light and sunshine, so it would be easier for dark moths to blend in with their environment long enough to reproduce and thrive.

Explanation:

The hydroxide ion concentration, [OH-] = 2.439 x 10⁻¹⁰

Equilibrium of water and the ions :

[tex]\tt 2H_2O(l)\rightarrow H_3O^+(aq)+OH^-(aq)[/tex]

[tex]\tt Kc=\dfrac{[H_3O^+][OH^-]}{H_2O}[/tex]

Kc[H₂O] is the ion equilibrium constant for water ⇒ Kw.

The product of the concentrations of these ions (H₃O⁺ and OH⁻)at equilibrium at 25°C is 1.0 x 10⁻¹⁴ M

[H₃O⁺] [OH⁻] = 1.0 x 10⁻¹⁴ M = Kw

The hydrogen ion concentration of  [H⁺]=4.1 x 10⁻⁵ M, so  the hydroxide ion concentration, [OH-] :

[tex]\tt 4.1\times 10^{-5}\times [OH^-]=1.10^{-14}\\\\(OH^-]=\dfrac{1.10^{-14}}{4.1\times 10^{-5}}\\\\(OH^-]=2.439\times 10^{-10}[/tex]

Answer:

152.63 ml.

Explanation:

By proportion to get a 4.75 M solution the volume will be

(12/4.75) * 100 = 252.63 ml

So the answer is 152.63 ml.

molarity=number of moles/volume

First we find the number of moles of NaOH we have the molarity and the volume we transform mililiters in liters 100ml=0.1l

12=n/0.1 n=1.2 moles of NaOH

now we find the volume of the second solution

4.75=1.2/V

V=1.2/4.75=0.252l

0.252-0.1=0.152liters=152ml of pure water used to dilute

Answer:

Answered below

Explanation:

1) 2Na (s) + 2H2O (l) → 2NaOH (aq) + H2 (g)

2) 2Na (s) + H2 (g) → 2NaH (s)

3) Formula for graphite is C.

Thus;

Na + C → NaC

4) 2Na (s) + O2 (g) → 2Na_2O_2 (s)

5) 2Na (s) + Cl2 (g) → 2NaCl (s)

6) Na + Pb → NaPb

7) Na (s) + NH3 (g) → NaNH2 (s) + H2 (g)

You haven't provided two critical pieces of info needed to answer this question. First, what's the half-life of Californium-252, and second, what's the initial amount of Californium-252. Given these two values, you can then set up an exponential equation to find the time elapsed.

Answer:

atoms

Explanation:

atoms combines to form compound

Answer:

An asexually reproducing organism would have the best chance of repopulating the world.

Explanation:

Sexual reproduction is a method of reproduction that involves two parents and the formation and subsequent fusion of male and female gametes during fertilization. On the other hand, In asexual reproduction, only one parent is involved and produces offspring by making copies of itself through various methods such as binary fusion, budding and vegetatively.

In a case of a catastrophic event that wiped out almost all organisms, an organism that reproduces asexually have a greater chance of repopulating the world because of the following advantages in reproducing asexually:

1. Only one parent is needed, therefore reproduction is easier.

2. It isaves time and energy. Since almost all organisms have been wiped out, there is a lesser likelihood of finding a compatible mate, so reproducing asexually will give the organism a better chance.

3. It occurs at a very fast rate; much faster than sexual reproduction

4. The population can increase very quickly and colonization of new habitats is much easier.

All these advantages will give the esexually reproducig organism a fairer chance to repopulate the world.

The oxidation number of Mg in Mg(OH)₂ is +2.

Hence, Option A is correct answer.

The oxidation state, or oxidation number, is defined as the hypothetical charge of an atom if all of its bonds formed with different atoms were fully ionic. It indicates the degree of oxidation of an atom in a chemical compound. Conceptually, the oxidation state may be negative, positive or zero.

Oxidation number of OH = -1

Let us suppose the oxidation number of Mg = x

Charge on compound = 0

We can write

x + 2(-1) =0

x-2=0

x = 2

Thus from the above solution we concluded that The oxidation number of Mg is +2.

Hence, Option A is correct answer.

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Answer:

1/32 of the original sample

Explanation:

edgunity got it.

Answer:

The answer would be cation

Explanation:

Answer:

it's an anion

if it has more electrons than protons, then it has a negative net charge making it an anion

Answer:

D

Explanation:

Because if I said its 35 degrees outside that has nothing to do with climate maybe if I said its usually 35 degrees in the month of December but just saying what temperature it doesn't tell you anything about climate

Well, the definition of climate is the weather conditions prevailing in an area in general or over a long period so I don't really know

So maybe it is d

Answer:

B

Explanation:

Weather refers to the short-term conditions of the lower atmosphere, such as precipitation, temperature, humidity, wind direction, wind speed, and atmospheric pressure. It could be sunny, cloudy, rainy, foggy, cold, hot, windy, stormy, snowing … the list goes on.

Answer:

they bonding

Explanation:

dfffffffffffffff

Answer:

molecular formulas of the hydrocarbons

Answer:

coh3 and xxxxxxxxxxxxx

An atom is the fundamental unit of matter and it contains an equal number of protons and electrons in its nucleus which makes it electrically neutral. An ion however, is an atom containing an unequal number of protons and electrons which means it will either carry a net positive charge or negative charge depending on whether there are more electrons or protons.

Answer:

atoms are neutral or they have equal number of proton and electron but ions can be cation(positively charged) or anion(negatively charged) based on the number of electron the atom lose and gain respectively

Answer:

oxidation

Explanation:

the process or result of oxidizing or being oxidized.

hope this helpppppppppppppeddddddd

The molecule which has a structure that is most like aspirin is benzene.

Aspirin, also known as acetylsalicylic acid, is a pain reliever, fever reducer, and inflammation reducer.

In the structure of aspirin one aromatic ring is present in which carboxylic group is present and molecular formula of aspirin is written as C₉H₈O₄.

Hence benzene has a structure that is most like aspirin.

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Answer:

D

Explanation:

If there are 2 of the same rocks on two continents, that shows that they were once merged. If there is glacial existence in places where glaciers would’ve melted (Like Africa has glacial existence from Antarctica ) this shows that continents were once merged. If life forms preserved as fossils were matched on 2 different continents this shows that all the continents were once merged.

Answer:

so i am doing this and i need help what did u get for number 1

Explanation:

its the first question

Answer:

B

Explanation:

Answer:

0.6022×10²³ molecules

Number of moles = 0.1 mol

Explanation:

Given data:

Mass of HCl = 3.65 g

Number of molecules = ?

Number of moles = ?

Solution:

Number of moles:

Number of moles = mass/molar mass

Number of moles = 3.65 g/36.45 g/mol

Number of moles = 0.1 mol

Number of molecules:

1 mole of any substance contain 6.022×10²³ molecules

0.1 mol ×  6.022×10²³ molecules/ 1 mol

0.6022×10²³ molecules

Answer:

they must have same atomic number and different atomic mass

Answer:

cesium is the largest alkali metal.

Explanation:

Answer:

Cesium

Explanation:

Cesium is the largest atom among alkali metal.

Answer:

for example the company has been in the United kingdom for women who have a lot to say it is not the only one that has the best of

Explanation:

get a little bit more of the year and

Answer:

for example the company has been in the United kingdom for women who have a lot to say it is not the only one that has the best of

Explanation:

Answer:

17 for chlorine atom ; 18 electrons for a chlorine ion

Answer:

The amount of work required to raise the TV from point A to point B is equal to the amount of gravitational potential energy the TV gains from its height above the ground. This is generally true for any object ...

Explanation:

ok that is ans k............

The temperature of the 20 L tank containing 68 g of carbon dioxide, CO₂ at 500 KPa is 778.5 K

Mole = mass / molar mass

Mole of CO₂ = 68 / 44

Mole of CO₂ = 1.545 moles

Using the ideal gas equation, the temperature of the gas can be obtained as follow:

PV = nRT

Divide both side by nR

T = PV / nR

T = (500 × 20) / (1.545 × 8.314)

T = 778.5 K

Thus, the temperature of the tank is 778.5 K

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Answer:

B

Explanation:

CH4 + 2 O2 → CO2 + 2 H20

12 + I X 4 → → 2 ( I X2 + 16 )

16 → → 36

25, 5 → → ?

amount of H2O = 36 X 25,5 / 16 = 57. 39

One mole or 16 g of methane gas reacts with excess oxygen to give 2 moles or 36 g of water. Then, the mass of water produced from 25.5 g of methane is 57.3 g.

Combustion is the reaction of a gas with the atmospheric oxygen producing water and carbon dioxide. The hydrocarbon gases such as methane, ethane etc easily undergo combustion reaction.

As per the given balanced reaction, one mole of methane gas CH4 produces two moles of water.

molar mass of methane = 16 g/mol

molar mass of water = 18 g/mol

mass of 2 moles of water = 36 g.

Hence, 16 g methane gas produce 36 g of water.

The mass of water produced from 25.5 grams of methane gas is then calculated as follows:

mass of water = 25.5 × 36 / 16 = 57.3 g.

Therefore, 57.3 g of water is produced in this reaction from 25.5 g of methane.

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