A student weighs an empty flask and stopper and finds the mass to be 53.256 g. She then adds about 5 mL of an unknown liquid and heats the flask in a boiling water bath at 98.8°C. After all the liquid is vaporized, she removes the flask from the bath, stoppers it, and lets it cool. After it is cool, she momen- tarily removes the stopper, then replaces it and weighs the flask and condensed vapor, obtaining a mass of 53.780 g. The volume of the flask is known to be 231.1 mL. The absolute atmospheric pressure in the laboratory that day is 728 mm Hg. a. What was the pressure of the vapor in the flask in atm?

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:

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:

because it has more space

Explanation:

density have many pressure

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:

Answer:

did u ever get an answer??

Explanation:

Answer:

The answer is C. Yes, because heat was produced

Answer: 1. The coefficient is 1.12

2. The exponent is 4

3. There are 3 significant digits

4. The rightmost significant figure is 2.

Explanation:

Scientific notation is defined as the representation of expressing the numbers that are too big or too small and are represented in the decimal form with one digit before the decimal point times 10 raise to the power.

For example : 5000 is written as [tex]5.0\times 10^3[/tex]

According to avogadro's law, 1 mole of every gas contains avogadro's number [tex]6.023\times 10^{23}[/tex] of particles and occupy 22.4 L at STP.

[tex]6.023\times 10^{23}[/tex] molecules of [tex]CO_2[/tex] occupy = 22.4 L at STP.

Thus [tex]3.00\times 10^{26}[/tex] molecules of [tex]CO_2[/tex] occupy = [tex]\frac{22.4}{6.023\times 10^{23}}\times 3.00\times 10^{26}=11.2\times 10^3 L[/tex] at STP.

Scientific notation = [tex]1.12\times 10^4L[/tex]

The coefficient is 1.12

The exponent is 4

There are 3 significant digits

The rightmost significant figure is 2.

There are multiple ways to prevent these situations from occurring. The three most common protective devices are fuses, circuit breakers, and surge protectors

Explanation:

Answer:

590J or 590.4J :)

Explanation:

2.46 x 6 (35-29= 6) x 40 = 590.4J

Nearest whole number : 590J

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:

0.08911760029829444

Explanation:

hop that this what you wanted

Answer:

f the figure is a square with a perimeter of 16 inches, then each side of the square is 4 inchest in length. Area is found by multiplying the length x the width. For a square, the length and width are the same. A = 16 sq

Explanation:

Answer:

1.a

2.c

hope helps

Explanation:

mark

pa

Answer:

The rollercoaster has the lowest kinetic energy at the top of the hill.

The rollercaoster has the highest kinetic energy at the bottom of the hill.

Explanation:

The kinetic energy of any solid body in motion is usually computed using this formula:

K.E = [tex]\frac{1}{2}mv^2[/tex]

From this, we can see that it varies based on two major parameters - The mass of the moving object and the velocity of the moving object.

We can assume that the mass of the rollercoaster is constant since no one gets off and it does not shrink in its size during the ride.

This means that the variations in the K.E are mainly coming from its velocity.

At the top of the hill, the rollercoaster is moving at its slowest pace. hence, it has the lowest kinetic energy at the top of the hill.

However, at the bottom of the hill, the rollercoaster is moving its fastest, hence it has the highest kinetic energy at the bottom of the hill.

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:

Answer:

rusting occur in oxygen and water coz when you put a nail into the water and you leave it three days you will the nail become brownish and that is due to oxygen and water

Answer:

The temperature would be too cold

Explanation:

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

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: C

Explanation: everything else seems like it is obeying the laws of gravity except wind blowing sand into the air. hope this helps.

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:

4)

Explanation:

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: Ionic bonds result from transfer of electrons, whereas covalent bonds are formed by sharing. ... Ionic bonds are electrostatic in nature, resulting from that attraction of positive and negative ions that result from the electron transfer process; charge separation between covalently bonded atoms is less extreme.

Explanation:

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

Answer:

a

Explanation: