PLEASE HELP I'M SO DOOMED
A balloon that contains 2.8 mol of helium gas has a volume of 31 L. If 3.5 g of helium is added, what will be the new volume of the balloon? Assume the temperature and pressure remain the same. The molar mass of helium is 4.00 g/mol.
a) 186 L
b) 70 L
c) 24 L
d) 41 L
Do not post links

Answer:

The speed of the reaction

Explanation:

I just took the test and got it right... i hope this helps u :)

Answer:

The formation of a gas is a clue to chemical changes. The bubbles of gas that you observed form when an antacid is dropped into water is an example of change. ... As wood burns, it turns into a pile of ashes and gases that rise into air.

Explanation:

Answer:

See explanation

Explanation:

1 mole of a gas occupies 22.4 L

x moles occupies 16.8 L

x = 1 mole *  16.8 L/22.4 L

x = 0.75 moles

number of moles = mass/molar mass

mass =  number of moles  * molar mass

mass =  0.75 moles * 30.01 g/mol = 22.5075 g = 2.25 * 10^1 g

the coefficient of the scientific notation answer = 2.25

the exponent of the scientific notation answer = 1

significant figures are there in the answer = 6

the right most significant figure in the answer = 3

2.

number of moles = 12.5g/38g/mol = 0.3289 moles

1 mole occupies 22.4 L

0.3289 moles occupies 0.3289 moles * 22.4 L/1 mole

= 7.36736 L = 7.36736 * 10^0 L= 7.37 * 10^0 L

the coefficient of the scientific notation answer =7.37

the exponent of the scientific notation answer = 0

significant figures are there in the answer = 6

the right most significant figure in the answer= 3

Answer:

because it has more space

Explanation:

density have many pressure

Answer:

The answer is Progressive Run

Explanation:

I took the test and got it right <3

Brisk walking is the type of exercise that includes walking 3 miles in an hour at a faster speed than strolling. The situation describes the progressive run.

A progressive run is a type of aerobic and anaerobic exercise that benefits training and race management techniques.

The progressive run technique includes the easy and relaxing jog with a gradually increased running pace. This practice is used to overcome the second-half slow run issues.

Therefore, the situation depicts option B. progressive run.

Learn more about the progressive run here:

https://brainly.com/question/18294066

Answer:

1.a

2.c

hope helps

Explanation:

mark

pa

Answer:

did u ever get an answer??

Explanation:

Answer:

The answer is C. Yes, because heat was produced

Since the molecular weight of water is about 18 g/mol, you have about 1 mol of water. So, now we know that it takes approximately 46.2 kJ of heat energy to warm 18.02g of water from 25C to 100C and then to vaporize it into steam. Hopefully this helped!

Explanation:

The would not be classified into archaea.

So, A.

Answer:

Copper(II) sulphate – sodium hydroxide reaction

The reaction between copper(Il) sulphate and sodium hydroxide solutions is a good place to start. If you slowly add one to the other while stirring, you will get a precipitate of copper(II) hydroxide, Cu(OH)2.

Answer:

The answer is "[tex]1.4 \ \bold{ billion-years}[/tex]".

Explanation:

Using formula:

[tex]\to N_{Now} = N_{orige}e^{\lambda t} \\\\[/tex]

[tex]\to[/tex] 1 U atom produces 1 Pb atom after decay.

[tex]\to[/tex] U's original numbers are now the sum of U counts and Pb counts.

 [tex]\to N_U=(N_U+N_{pb})e^{\lambda Ut}[/tex]

[tex]\to 1 = (1+3) \ exp[(\frac{-\ln(2)}{t_{(half)}} \times t ]\\\\\to t = [\frac{\ln(4)}{\ln(2)}] \times t_{(half)}[/tex]

      [tex]= 14 \times 10^8 \ \ years\\\\=1.4 \ billion \ \ years[/tex]

Answer:

70%of 2000 = 1400

2000 tonnes of hematite contains 1400 tonnes iron oxide .

1400 tonnes of fe2O3

fe2O3 have molar mass 159.69

calculate moles = given mass/molar mass

moles = 1400000000/159.69

moles = 8766986

one mole contains = 112 g of fe

so 8766986 moles will contain = 112×8766986

= 981,902,432 grams of ferrous

which is nothing but equal to 981.90 tonnes of iron!!

Answer:

7.22 L

Explanation:

From the question,

Applying Charles law,

V₁/T₁ = V₂/T₂...................... Equation 1

Where V₁ = Initial volume of gas, V₂ = Final volume of gas, T₁ = Initial Temperature of gas in Kelvin, T₂ = Final Temperature of gas in Kelvin

Make V₂ the subject of the equation

V₂ = (V₁×T₂)/T₁................. Equation 2

Given: V₁ = 5.00 L, T₁ = 20 °C = (20+273) K = 293 K, T₂ = 150 °C = (150+273) K = 423 K

Substitute these value into equation 2

V₂ = (5.00×423)/293

V₂ = 7.22 L

Answer:

All of them derive from a common ancestor. They each share something in their DNA that ties into their past selves, which were more closely related. As they evolved, they became more and more distant, but we can still trace them back to the olden days.

Also they all have scales.

Hope this was at least semi-useful.

Answer:

B

Explanation:

Answer:

83.674 grams of Fe

Explanation:

9.02 x 10²⁸ atoms

To convert from atoms to grams, we first need to convert atoms to moles. To do this, divide the atoms by Avogadro's Number, 6.02 x 10²³

9.02 x 10²⁸ ÷ 6.02 x 10²³

= 1.498 moles of Fe

Now we need to convert moles to grams. To do this, multiply the moles by the molar mass of Fe. The molar mass can be found on the periodic table.

1.498 • 55.845

= 83.674 grams of Fe

Hope this helps!

I'm glad for you! Best of luck in life tbh

Answer:

Cloruro de sodio y fluoruro de sodio.

Dióxido de carbono y monóxido de hidrógeno.

Explicación:

El cloruro de sodio y el fluoruro de sodio son los compuestos que tienen enlaces iónicos. Estos compuestos iónicos se utilizan para diferentes actividades de nuestra vida diaria. El cloruro de sodio se usa para cocinar y el fluoruro de sodio se usa en la pasta de dientes para limpiar nuestros dientes. El dióxido de carbono y el monóxido de hidrógeno son compuestos que tienen enlaces covalentes. El dióxido de carbono se usa en refrescos / refrescos y algunos otros líquidos que se pueden usar en la vida diaria. El monóxido de hidrógeno es el agua pura que bebemos todos los días en nuestra vida diaria y es muy importante para nuestra supervivencia.

Answer:

They are both listed under group 11 on the periodic table and both are highly conductive of electricity

Explanation:

HOPE THIS HELPS ^^

Answer:

0.08911760029829444

Explanation:

hop that this what you wanted

Answer:

3.052 × 10^24 particles

Explanation:

To get the number of particles (nA) in a substance, we multiply the number of moles of the substance by Avogadro's number (6.02 × 10^23)

The mass of Li2O given in this question is as follows: 151grams.

To convert this mass value to moles, we use;

moles = mass/molar mass

Molar mass of Li2O = 6.9(2) + 16

= 13.8 + 16

= 29.8g/mol

Mole = 151/29.8g

mole = 5.07moles

number of particles (nA) of Li2O = 5.07 × 6.02 × 10^23

= 30.52 × 10^23

= 3.052 × 10^24 particles.

Answer:

435.38 L

Explanation:

From the question,

Applying ideal gas equation,

PV = nRT................... Equation 1

Where P = Pressure, V = Volume, n = number of moles, R = molar gas constant, T = Temperature.

Since Temperature and Pressure were constant,

V ∝ n

V/n = V'/n'.................... Equation 2

Where V and V'  = the initial and final Volume of Ar respectively, n and n'  = the initial and final moles of Ar respectively

make V' the subject of the equation

V' = Vn'/n............... Equation 3

Given: V = 100 L, n = 3.25 mol, n' = 14.15

Substitute into equation 3

V' = (100×14.14)/3.25

V' = 435.38 L

4.15 mole of Ar gas occupy the volume of 435.38 L under same condition.

Ideal gas equation for any gas at standard condition is define as:

PV = nRT, where

P = Pressure,

V = Volume,

n = number of moles,

R = molar gas constant,

T = Temperature.

In the question it is given that pressure and temperature for the expansion is constant, so ideal gas equation becomes:

V/n = V'/n', where

V = initial volume of Ar = 100 L (given)

V' = final Volume of Ar = to find?

n = initial moles of Ar = 3.25 mole (given)

n' = final moles of Ar = 14.15 mole (given)

Now we calculate the final volume as:

V' = (100×14.14)/3.25 = 435.38 L

Hence, 435.38 L is the occupied volume.

To know more about ideal gas equation, visit the below link:

https://brainly.com/question/20348074

Explanation:

For example, pH 10 is ten times more alkaline than pH 9 and 100 times (10 times 10) more alkaline than pH 8. Pure water is neutral. But when chemicals are mixed with water, the mixture can become either acidic or basic.

Answer:

i need help with that too.

Explanation:

When a drought occurs, their food supply can shrink and their habitat can be damaged. Lack of food and drinking water for wild animals. Increase in disease in wild animals, because of reduced food and water supplies. Migration of wildlife.