According to the kinetic-molecular theory, gases condense into liquids because of

39 liters of water at

Harman [31]

Answer:

Temperature of the mixture=8 °C

Explanation:

Let, Temperature of the mixture=t °C

Q₁ = Q₂

=> m₁SΔΘ₁ = m₂SΔΘ₂

=> 39 × (20+t) = 21 × (60-t)

∴ t = 8 °C

hope you have understood this

pls mark it as the brainliest

3 0

3 years ago

A loudspeaker located in air generates sound waves of frequency 1,000 Hz. Some of these sound waves enter a pool of water, where

prisoha [69]

Answer:

1.4 m

Explanation:

v = Speed of sound in water = 1400 m/s

f = Frequency of sound = 1000 Hz

$\lambda$ = Wavelength

When we multiply the frequency and the wavelength of a wave we get the velocity of sound in that medium

$v=f\lambda\\\Rightarrow \lambda=\dfrac{v}{f}\\\Rightarrow \lambda=\dfrac{1400}{1000}\\\Rightarrow \lambda=1.4\ m$

The wavelength of the sound waves in water is 1.4 m

8 0

2 years ago

Imagine a glass box that is completely sealed and in that box is a cactus in a small pot which statement is most accurate?

Dennis_Churaev [7]

I THINK C BECAUSE IF IT IS A GLASS BOX HOW DID A CACTUS GET IN AND NOTHING CAN GET IN OR OUT OF THE BOX SO THERE IS NO CACTUS IN THE BOX

6 0

2 years ago

Read 2 more answers

WILL GIVE BRAINLIST

Gnesinka [82]

Answer:

the graph shows the cost of natural hazards in the us in 2011 (in billions of dollars)

Explanation:

it shows that the cost of a tornado happeniy is 30 billion dollars

and the cost of an earthquake is way lower than the one the tornado which is 0 dollar

7 0

1 year ago

Read 2 more answers

Use the Bohr model to address this question. When a hydrogen atom makes a transition from the 5 th energy level to the 2nd, coun

iris [78.8K]

Answer:

A. 2.82 eV

B. 439nm

C. 59.5 angstroms

Explanation:

A. To calculate the energy of the photon emitted you use the following formula:

$E_{n1,n2}=-13.4(\frac{1}{n_2^2}-\frac{1}{n_1^2})$ (1)

n1: final state = 5

n2: initial state = 2

Where the energy is electron volts. You replace the values of n1 and n2 in the equation (1):

$E_{5,2}=-13.6(\frac{1}{5^2}-\frac{1}{2^2})=2.82eV$

B. The energy of the emitted photon is given by the following formula:

$E=h\frac{c}{\lambda}$ (2)

h: Planck's constant = 6.62*10^{-34} kgm^2/s

c: speed of light = 3*10^8 m/s

λ: wavelength of the photon

You first convert the energy from eV to J:

$2.82eV*\frac{1J}{6.242*10^{18}eV}=4.517*10^{-19}J$

Next, you use the equation (2) and solve for λ:

$\lambda=\frac{hc}{E}=\frac{(6.62*10^{-34} kg m^2/s)(3*10^8m/s)}{4.517*10^{-19}J}=4.39*10^{-7}m=439*10^{-9}m=439nm$

C. The radius of the orbit is given by:

$r_n=n^2a_o$ (3)

where ao is the Bohr's radius = 2.380 Angstroms

You use the equation (3) with n=5:

$r_5=5^2(2.380)=59.5$

hence, the radius of the atom in its 5-th state is 59.5 anstrongs

8 0

2 years ago