In an electrochemical cell, the anode is ___

You place a 500 g block of an unknown substance in an insulated container filled 2 kg of water. The block has an initial tempera

Nina [5.8K]

Answer:

3349J/kgC

Explanation:

Questions like these are properly handled having this fact in mind;

Heat loss = Heat gained

Quantity of heat = mcΔ∅

m = mass of subatance

c = specific heat capacity

Δ∅ = change in temperature

m₁c₁(∅₂-∅₁) = m₂c₂(∅₁-∅₃)

m₁ = mass of block = 500g = 0.5kg

c₁ = specific heat capacity of unknown substance

∅₂ = block initial temperature = 50oC

∅₁ = equilibrium temperature of block and water after mix= 25oC

m₂= mass of water = 2kg

c₂ = specific heat capacity of water = 4186J/kg C

∅₃ = intial temperature of water = 20oC

0.5c₁(50-25) = 2 x 4186(25-20)

And we can find c₁ which is the unknown specific heat capacity

c₁ = $\frac{2*4186*5}{0.5*25}$ = 3348.8J/kg C≅ 3349J/kg C

4 0

2 years ago

Determine the mass of fuel required for the expected energy consumption in the United States for the next 10 years:

alexandr1967 [171]

Answer:

(This will depend on the type of fuel, I will assume that the fuel is petrol)

First, let's find the expected energy consumption in the US for the next 10 years.

We know that in one year, a person consumes 3.5*10^11 joules.

There are 310,000,00 people on the US

Then the total consumption in one year is:

310,000,000*3.5*10^11 joules = 1.085*10^20 J

In 10 years the consumption is 10 times the consumption of a single year, then the expected energy consumption in the US for the next 10 years is:

10*1.085*10^20 J = 1.085*10^21 J

Now let's find the mass of fuel required.

We know that a liter of petrol has 31,536,000 joules of energy,

And a liter of petrol weights 0.75 kg

To find the number of liters of petrol that we need, we need to find the quotient between the expected energy consumption in the next 10 years and the energy of a single liter of petrol, this is:

N = (1.085*10^20 J)/(31,536,000 j) = 3.44*10^13

We will need 3.44*10^13 liters of petrol.

And the total mass of petrol will be:

M = 3.44*10^13*0.75 kg = 2.58*10^13 kg of fuel.

8 0

3 years ago

What is the frequency of a microwave with a wavelength of 3.52 mm?

AlekseyPX

As per the question the wavelength of the microwave is given as 3.52 mm.

we are asked to calculate the frequency of the wave.

we know that microwave is a electromagnetic wave.

As per Clark Maxwell's electromagnetic theory ,every electromagnetic wave moves with a velocity equal to the velocity of light in vacuum and that is equal to 3×10^8 m/s.

From the equation of the wave,we know that velocity of wave is the product of frequency and wavelength.

Mathematically wave velocity $v=f*\lambda$ where f is the frequency of the wave and $\lambda$ is the wavelength.

As per the question $\lambda=3.52 mm$

$= 3.52*10^{-3} m$

Here $v=c=3*10^{8} m/s$

Hence frequency of the wave $f=\frac{v}{\lambda}$

$=\frac{3*10^{8} }{3.52*10^{-3} } s^{-1}$

$=0.852272727272*10^{11} Hz$

Here Hertz [Hz] is the unit of frequency.

6 0

3 years ago

Read 2 more answers

What order shows increasing frequency for gamma rays, microwaves, visible light, and X-rays?

sergejj [24]

Answer:

Person above me is right, it's B: microwaves, visible light, X-rays, gamma rays

Explanation:

6 0

2 years ago

Given that ethylene has a λmax of 175nm, butadiene has a λmax of 220nm, and 2-methyl-1,3-butadiene has a λmax or 215nm, what is

Vika [28.1K]

The λmax of 2,3,4-trimethylhexatriene is 280 nm.

Ethylene has a λmax of 175nm.

Butadiene has a λmax of 220nm.

2-methyl-1,3-butadiene has a λmax or 215nm.

1,3,5-hexatriene has a λmax of 258nm.

Woodward's rules, sometimes known as Woodward-Fieser rules (after Louis Fieser) and named after Robert Burns Woodward, are a number of sets of empirically developed principles that aim to forecast the wavelength of the absorption maximum (max) in an ultraviolet-visible spectrum of a certain molecule.

By using the Woodward Fieser rule,

R- (Alkyl Group) .... +5 nm = 5 × 2 = 10

RO- (Alkoxy Group) .. +6 = 6 × 2 = 12

Adding 22nm to the λmax of 1,3,5-hexatriene as it has 2 alkyl groups and 2 alkoxy groups to form 2,3,4-trimethylhexatriene.

The λmax of 2,3,4-trimethylhexatriene is 280 nm.

Learn more about Woodward-Fieser here:

brainly.com/question/16982345

#SPJ4

5 0

2 years ago

In an electrochemical cell, the anode is ____.