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3 years ago

What is the specific heat, thermal conductivity, density of polyurethane foam?

1 answer:

4 0

Insulation materials with higher thicknesses have lower long-term thermal conductivity values in general. The density of rigid polyurethane foam (PUR/PIR) used for building thermal insulation typically ranges from 30 to 45 kg/m3. For some applications, however, it can achieve 100 kg/m3.

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Is this equation balanced: AgNO3 + 2 KCl -->AgCl + KNO3 Yes No

frutty [35]

Answer:

Explanation:

AgNO₃ + KCl --> AgCl + KNO₃

This reaction is a precipitation reaction. AgCl is formed as a white solid due to its low solubility in water.

5 0

3 years ago

1. If you have a sample of gas at a pressure of 16 atm, what will the pressure be if the volume is halved?

vagabundo [1.1K]

Answer:

1. The pressure will be 32 atm, twice the initial pressure.

2. The pressure will be 1.83 atm, one third of the initial pressure.

Explanation:

Boyle's law is one of the gas laws that relates the volume and pressure of a certain quantity of gas kept at a constant temperature.

This law says that "The volume occupied by a given gaseous mass at constant temperature is inversely proportional to pressure." This means that if the pressure increases, the volume decreases, while if the pressure decreases, the volume increases.

Boyle's law is expressed mathematically as:

Pressure * Volume = constant

or P * V = k

Ahora es posible suponer que tienes un cierto volumen de gas V1 que se encuentra a una presión P1 al comienzo del experimento. Si varias el volumen de gas hasta un nuevo valor V2, entonces la presión cambiará a P2, y se cumplirá:

P1*V1=P2*V2

1. In this case:

P1= 16 atm
V1
P2= ?
V2= V1÷2= $\frac{V1}{2}$ because the volume is halved.

So:

16 atm*V1= P2* $\frac{V1}{2}$

Solving:

$\frac{16 atm*V1*2}{V1}$ =P2

16 atm*2= P2

32 atm= P2

The pressure will be 32 atm, twice the initial pressure.

2. Now

P1= 5.5 atm
V1
P2= ?
V2= V1*3 because the volume is tripled.

So:

5.5 atm*V1= P2* V1*3

Solving:

$\frac{5.5 atm*V1}{3*V1}$ =P2

$\frac{5.5 atm}{3}$ = P2

1.83 atm= P2

The pressure will be 1.83 atm, one third of the initial pressure.

7 0

3 years ago

2. When two forces act on an object in opposite directions, you calculate the net

exis [7]

When two forces act on an object in opposite directions, the net force can be calculated by subtracting the two forces.

Explanation:

The net/final force by subtracting the two given opposite forces as asked in the above question.

For example: If you keep a bottle on the table, the downward force subtracted from the upward force will be equal to the net force.

If the net force equals zero then the objects will be balanced, otherwise unbalanced.

For example: In the tug of war when two forces are of different units the force with the greater strength will have an advantage, like if the team on the right is stronger than that of left than the rope will move towards the right.

5 0

3 years ago

Do all dipole-dipole forces have the same strength?

n200080 [17]

Inter molecula force
1- hydrogen bond
2- ion bond
3- dipole dipole
4- dipole bond or van der wael
but not all dipole dipole has the same strength

6 0

3 years ago

Visible light with a wavelength of 4.7x10^-7 meters will have a frequency of ....

Zarrin [17]

The answer is ....... 47/10^8

6 0

3 years ago