PLSS HELP ITS TIMED WILL MARK BRAINLIEST

How much heat is released when 35kg of water freezes?

inn [45]

You need an additional point of data here: the enthalpy of fusion, or conversely the enthalpy of melting (they differ only by their sign). For water (or ice) that value is gotten from sources such as the internet

ΔH°(fus) = 6.01 kJ/mole 

Since you have 35 000g, how many moles do you have? 
Moles H2O = 35000 g/(18.015 g/mole) = 1942.8 moles

So, take that ΔH°(fus) in kJ/mole, multiply by the number of moles, and there ya go!

6.01 x 1942.8 = 11,676 kJ of energy is released

Hope I helped!! xx

3 0

3 years ago

20. A car battery with a 12-V emf and an internal resistance of 0.050 Ω is being charged with a current of 60 A. Note that in th

topjm [15]

Answer:

Part a)

V = 15 Volts

Part b)

P = 180 Watt

Part c)

Rate = 720 Watt

Explanation:

Part a)

When battery is in charging then the potential difference of the terminals of cell is given by

$\Delta V = EMF + iR$

here we know that

EMF = 12 volts

i = 60 A

r = 0.050 ohm

now we have

$\Delta V = 12 + (0.050)(60) = 15 Volts$

Part b)

Rate of thermal energy dissipated is the energy which is dissipating across the resistor

so here we have

$P = i^2 R$

$P = (60^2)(0.05)$

P = 180 Watt

Part c)

Rate at which Energy stored inside the cell is the rate of electrical energy that is converted into the chemical energy

$Rate = EMF \times i$

$Rate = (12)(60)$

$Rate = 720 Watt$

6 0

3 years ago

Floodplains are most often found for rivers that exist on

Kazeer [188]

I am pretty sure that floodplains are most often found for rivers that exist on 
hilly areas at the base of mountains. In order to give yoy ans example which will make sure that this answer is quite a suitable one, nice example of floodplains
is The Virgin River at the upper end of Zion Canyon. It will definitely help you! Regards.

3 0

3 years ago

Read 2 more answers

What is the frictional force between a box and the floor it is being pulled across if, the kinetic coefficient of friction is 0.

Artyom0805 [142]

If the pulling is done parallel to the floor with constant velocity, then the box is in equilibrium. In particular, the weight and normal force cancel, so that

n = 38 N

The friction force is proportional to the normal force by a factor of 0.27, so that

f = 0.27 (38 N) ≈ 10.3 N

and so the answer is D.

8 0

3 years ago

At the surface, atmospheric pressure is 1.013 × 10^5 Pa. People can normally snorkel down to a depth of roughly one meter. What

natulia [17]

Answer:

1.01 × 10⁵ Pa

Explanation:

At the surface, atmospheric pressure is 1.013 × 10⁵ Pa.

We need to find the total pressure on the air in the lungs of a person to a depth of 1 meter.

Pressure at a depth is given by :

$P=\rho gh$

Where

$\rho$ is the density of air, $\rho=1.225\ kg/m^3$

So,

$P=1.225\times 9.8\times 1\\\\=12\ Pa$

Total pressure, P = Atmospheric pressure + 12 Pa

= 1.013 × 10⁵ Pa + 12 Pa

= 1.01 × 10⁵ Pa

Hence, the total pressure is 1.01 × 10⁵ Pa.

5 0

3 years ago