A certain first-order reaction has a half-life of 20.0 minutes. How much time is required for this reaction to be 75% complete?

Answer:

21.2 grams CH2Cl2

Explanation:

Number of moles: .25

Molar mass of CH2Cl2: 84.93 g/mol

Mass in grams: 84.93(0.250) = 21.2325

Considering the definition of molar mass, the mass of 0.250 moles of CH₂Cl₂ is 21.225 grams.

The molar mass of substance is a property defined as its mass per unit quantity of substance, in other words, molar mass is the amount of mass that a substance contains in one mole.

The molar mass of a compound (also called Mass or Molecular Weight) is the sum of the molar mass of the elements that form it (whose value is found in the periodic table) multiplied by the number of times they appear in the compound.

In this case, you know the molar mass of the elements is:

So, the molar mass of the compound CH₂Cl₂ is calculated as:

CH₂Cl₂= 12 g/mole + 2× 1 g/mole + 2× 35.45 g/mole

Solving:

CH₂Cl₂= 84.9 g/mole

Next, you can apply the following rule of three: If by definition of molar mass 1 mole of the compound contains 84.9 grams, 0.250 moles of the compound contains how much mass?

[tex]mass=\frac{0.250 molesx84.9 grams}{1 mole}[/tex]

mass= 21.225 grams

The mass of 0.250 moles of CH₂Cl₂ is 21.225 grams.

Learn more about molar mass:

https://brainly.com/question/5216907

https://brainly.com/question/11209783

https://brainly.com/question/7132033

https://brainly.com/question/17249726

Answer:

waste water from nuclear power plant is

generally very harmful for our environment

and for everyone

hope it will help

Explanation:

H2O, what is the maximum amount of H2O which could be formed from 10.9 g of H2 and 16.03 g ofO2? Answer in units of g. ... 0.500 mol O2 x 2 mol H2O / 1 mol O2 x 18 g H2O/mol H2O = answer in ..

Answer:

yez so the answer is mg 1.0

Explanation:

The excess reactant is present in an amount that is greater than required. The amount of MgO that is produced in the reaction is 0.74 moles.

An excess reactant is that reantant thatis present in an amount that is more than required.

Now we are told that the magnessium is the reactant in excess so we have to use the amount of oxygen.

The reaction is: 2Mg + O2 ---->2MgO

1 mole of O2 produces 2 mole of MgO

0.37 moles of O2 produces 0.37 moles  * 2 moles/1 mole

= 0.74 moles

Learn more about excess reactant: https://brainly.com/question/365923

The atmosphere of the earth is layered and each layer of the atmosphere has its own properties. The atmosphere of the earth is divided into four layers. The thermosphere typically breaks up meteors before they hit Earth is not correct. The correct option is C.

The four important layers of atmosphere are troposphere, stratosphere, thermosphere and mesosphere. The layer of the atmosphere which is found above the stratosphere is defined as the mesosphere. It is the coldest layer of the atmosphere.

A meteor is known as a celestial object which is made up of rocks and minerals which enters the atmosphere of the earth and burns out completely before reaching the surface of the earth. It is known as the shooting star or falling star.

The temperature of mesosphere drops with altitude. By 80 km it reaches 100 degree celsius. The meteors burn up in this layer not in thermosphere.

Thus the correct option is C.

To know more about earth layers, visit;

https://brainly.com/question/13497783

#SPJ3

This is a combined gas law problem, according to which

[tex]\frac{P_1V_1}{T_1} = \frac{P_2V_2}{T_2}[/tex]

where P is the pressure of the gas, V is the volume of the gas, and T is the temperature of the gas, and the subscripts 1 and 2 correspond to the initial and final conditions of the gas. In this problem, we are given the initial pressure, volume, and temperature of the gas in the balloon:

P₁ = 1.0 atm

V₁ = 1.8 L

T₁ = 295.15 K (K = °C + 273.15).

Moreover, we are given the final pressure and temperature of the gas in the balloon.

P₂ = 0.86 atm

T₂ = 281.15 K.

What we want to find is the final volume, V₂, which we can obtain by rearranging the combined gas equation to solve for V₂:

[tex]V_2=\frac{P_1V_1T_2}{T_1P_2} = \frac{(1.0 \text{ atm})(1.8 \text{ L})(281.15 \text{ K})}{(295.15 \text{ K})(0.86 \text{ atm})} \\ V_2 = 1.99 \text{ L}[/tex]

This answer has three significant figures. However, the question as written would warrant an answer that comprises one significant figure (as 8 °C has only one sig fig). In that case, the answer would be 2 L. If the answer is to be given to two significant figures, the volume would then be 2.0 L.

Answer:

1 M

Explanation:

Molarity is moles per liter (mol/L).

You have 3 moles of HCl in 3 L of water.  Divide the two values.

(3 mol)/(3 L)

= 1 mol/L

= 1 M

Answer:

noe  sory opwqkfj

s

Explanation:

Answer: The new pressure is 831 mm Hg

Explanation:

The combined gas equation is,

[tex]\frac{P_1V_1}{T_1}=\frac{P_2V_2}{T_2}[/tex]

where,

[tex]P_1[/tex] = initial pressure of gas = 740 mm Hg

[tex]P_2[/tex] = final pressure of gas = ?

[tex]V_1[/tex] = initial volume of gas = 2.2 L

[tex]V_2[/tex] = final volume of gas = 2.0 L

[tex]T_1[/tex] = initial temperature of gas = 290 K

[tex]T_2[/tex] = final temperature of gas = 296 K

Now put all the given values in the above equation, we get:

[tex]\frac{740\times 2.2}{290}=\frac{P_2\times 2.0}{296}[/tex]

[tex]P_2=831mmHg[/tex]

The new pressure is 831 mm Hg

The second thesis statement is perfect. It supports the claim and presents main idea.

Answer:

the answer is D the dominant over powers the resecive traits

Answer:    D

Explanation:

Trust me please

Answer:

1.25 moles NaNO

Explanation:

Molarity = moles/Volume (L)

moles = Molarity (M) x Volume (L)

M = 2.5 M

V = 500 mL = 0.5L

moles = M x V = 2.5 x 0.5 = 1.25 moles

Answer:

CBr4

Explanation:

Answer:

CBr4

Explanation:

It is CBr4 I hope it helps

Answer: If we work it out with direct proportions, the vapor pressure of propanone is 56 degrees Celsius. The atmospheric pressure is about 101.

Explanation: hope this helps.

The vapor pressure of propanone at 50°C is :

- 78° vapor pressure

When the vapor pressure is specifically work through the extents to a temperature rate it response is intensely subordinate on their possess a mass nature.

The vapor weight of propanone is calculated and shape in degree Celsius in rate.

The rate of vapor when it is calculated by 50°C with propanone its at long last gives us a 78° vapor pressure.

Learn more about "Propanone":

https://brainly.com/question/491528?referrer=searchResults

Answer:

question 1 i believe is c i will put the other answeres in comments

when i finish the test

Explanation:

The carbon cycle plays an important in maintaining carbon balance on the earth.

The carbon cycle is the cycle by which carbon is recycled between the atmosphere and the geosphere.

In the carbon cycle, the process of recycling carbon do not include deep burial, compaction, and cementation.

Volcanic eruptions are one natural way that carbon can move OUT of the geosphere.

Fossil fuels, atmosphere, land biomass and rocks are all carbon reservoirs, but fossil fuels contains the MOST carbon.

The atmosphere is the carbon reservoir that changes the quickest and has the biggest direct effect on climate.

Ocean acidification occurs because the ocean absorbs more human-produced CO2, causing the acidity to increase.

A potential impact of ocean acidification is that ocean ecosystems may suffer, making it harder for humans to get food from the ocean.

Therefore, the carbon cycle is important in maintaining carbon balance on the earth.

Learn more about carbon cycle at: https://brainly.com/question/25845923

The type of bond formed depends on the valence electrons (no: of electrons in the outermost shell)

When two atoms share one electron pair between each other, then they are said to be bonded by single covalent bond

When two atoms share two electron pairs between each other, they are said to be bonded by double covalent bond

When two atoms share three electron pairs between each other, they are said to be bonded by triple covalent bond.

Hope u understand

Please mark as the brainliest

Answer:

a) both their average kinetic energy and temperature will be the same

Explanation:

Temperature is the measure of the average kinetic energy of a system. As temperature increases, so will kinetic energy. As kinetic energy increases, speed increases. As one decreases, so does the other. When two objects are in contact with each other, their molecules will exchange energy and cause an eventual equilibrium of temperature and kinetic energy.

Answer:

different , same, same, same

Answer: The volume of the gas is 0.84 Liters

Explanation:

According to ideal gas equation:

[tex]PV=nRT[/tex]

P = pressure of gas = 1530 mm Hg = 2.01 atm     (760mmHg=1atm)

V = Volume of gas = ?

n = number of moles = 0.275

R = gas constant =[tex]0.0821Latm/Kmol[/tex]

T =temperature =[tex]75K[/tex]

[tex]V=\frac{nRT}{P}[/tex]

[tex]V=\frac{0.275atm\times 0.0820 Latm/K mol\times 75K}{2.01atm}=0.84L[/tex]

Thus the volume of the gas is 0.84 Liters

I think true..

Explanation:

im not sure.

Answer:

It means beside or alongside.

Answer:

The word Paralympics means “parallel with the Olympics”, with the para prefix coming from the Greek word for alongside. The name was chosen to embody the spirit of the two movements existing side-by-side.

Explanation:

Answer:

i going to be aniston i would say take a gess

The acidity or alkalinity of a solution depends upon its hydronium ion concentration and hydroxide ion concentration. The concentration of OH⁻ is 1 × 10⁻⁴ M.

The pOH expresses the hydroxide ion concentration of a solution. The pOH of a solution is defined as the negative logarithm to the base 10 of the value of the hydroxide ion concentration in moles per litre.

The equation used to calculate the concentration of OH⁻ is:

pOH = -log [OH⁻]

[OH⁻] = 10⁻pOH

[OH⁻] = 10⁻⁴

= 0.0001 M

The number of significant figures in a reported value is the number of digits that are known with certainty plus the last one having some uncertainty.

Here 0.0001 contains 3 significant figures. In scientific notation it can be represented as 1 × 10⁻⁴ M.

Thus the concentration of [OH⁻] is 1 × 10⁻⁴ M.

To know more about pOH, visit;

https://brainly.com/question/4092108

#SPJ5

Answer:

tin

Explanation:

since it takes less heat to change it will warm up and produce thermal energy sooner than carbon

2 kg of carbon at 50°C will provide more thermal energy than 2 kg of tin at the same temperature.

To determine which substance will provide more thermal energy, we need to calculate the thermal energy for both scenarios using the formula:

Thermal energy = mass * specific heat * temperature change

For 2 kg of tin at 50°C:

Thermal energy = 2 kg * 230 J/kg°C * (50°C - 0°C) = 23,000 J

For 2 kg of carbon at 50°C:

Thermal energy = 2 kg * 709 J/kg°C * (50°C - 0°C) = 70,900 J

Therefore, 2 kg of carbon at 50°C will provide more thermal energy than 2 kg of tin at the same temperature. This is because carbon has a higher specific heat (709 J/kg°C) compared to tin (230 J/kg°C), meaning it requires more energy to raise the temperature of carbon compared to tin. As a result, carbon can store and release more thermal energy than tin at the same temperature and mass.

To know more about thermal energy, here

brainly.com/question/3022807

#SPJ2

Answer: 10 minutes

Explanation:

ln(No/N) = kt

No = 80 mg

N = 10 mg

t = 30 min

solve for k, then

k = 0.693/t1/2

Substitute k from above and solve for t1/2

10 min is correct.