All categories

3 years ago

A balloon filled with helium occupies 20.0 l at 1.50 atm and 25.0◦

1 answer:

5 0

At stp (standard temperature and pressure), the temperature is T=0 C=273 K and the pressure is p=1.00 atm. So we can use the ideal gas law to find the number of moles of helium:
$pV=nRT$
where p is the pressure (1.00 atm), V the volume (20.0 L), n the number of moles, T the temperature (273 K) and $R=0.082 atm L K^{-1} mol^{-1}$ the gas constant. Using the numbers and re-arranging the formula, we can calculate n:
$n= \frac{pV}{RT}= \frac{(1.00atm)(20.0L)}{(0.082 LatmK^{-1}mol^{-1})(273 K)}=0.89 mol$

You might be interested in

Two pianos each sound the same note simultaneously, but they are both out of tune. On a day when the speed of sound is 349 m/s,

SSSSS [86.1K]

Answer:

Time period between the successive beats will be 0.1703 sec

Explanation:

We have given speed of the sound v = 349 m/sec

Wavelength of piano $A\lambda _A=0.766m$

Wavelength of piano $B\lambda _B=0.776m$

So frequency of piano A $f_1=\frac{v}{\lambda _1}=\frac{349}{0.766}=455.61Hz$

Frequency of piano B $f_2=\frac{v}{\lambda _1}=\frac{349}{0.776}=449.74Hz$

So beat frequency f = 455.61 - 449.74 = 5.87 Hz

So time period $T=\frac{1}{f}=\frac{1}{5.87}=0.1703sec$

So time period between the successive beats will be 0.1703 sec

4 0

3 years ago

Marlon is studying a crab population. He has a large batch of crabs that were captured in the ocean. He places a plastic tag on

tatiyna

First time I did it I got 2143658709

7 0

3 years ago

PLEASE HELP (100)

morpeh [17]

Answer:

The work done will be $W=55.27\: J$

Explanation:

The work equation is given by:

$W=F\cdot x$

Where:

F is the force due to gravity (weight = mg)

x is the length of the ramp (3 m)

Now, the force acting here is the component of weight in the ramp direction, so it will be:

$F_{x-direction}=mgsin(28)$

Therefore, the work done will be:

$W=mgsin(28)*3$

$W=4*9.81*sin(28)*3$

$W=55.27\: J$

I hope it helps you!

3 0

3 years ago

If a magnet is put inside one coil of wire a voltage is produced. What will happen if the magnet is put inside two coils of wire

atroni [7]

The choices can be found elsewhere and as follows:

A)There will not be a change.
B)The voltage will decrease by a factor of two. 
C)The voltage will increase by a factor of two. 
D)The two coils of wire will cancel out the magnetic field. 
E)The voltage will be zero.

I believe the answer is option C. If the magnet is put inside two coils of wire, then the voltage will increase by a factor of two. Hope this answers the question.

8 0

3 years ago

Why can you exert a greater force on the pedals of a bicycle if you pull up on the handlebars?

Alex Ar [27]

Newtons laws of motion. Every action has an equal and opposite reaction. pulling UP on the handlebars pushes you DOWN on the pedals with the same force.

5 0

3 years ago