All categories

3 years ago

Steve traveled the first 7 hours of his

Chemistry

1 answer:

const2013 [10]3 years ago

5 0

Answer:

Explanation:

Distance traveled in 2 hours = 2 * 40 = 80 m

Distance traveled in 3 hours = 3 * 80 = 240m

Total distance covered = 240 + 80 = 320m

Total time = 2 + 3 =5 h

Hence avg speed = total distance covered / total time taken

= 320/5 = 64mph

You might be interested in

Ammonia NH3 is a common ingredient. If you have a cleaning agent containing 3.47 mol NH3, how many grams of NH3 are in the clean

8090 [49]

NH3 has a Molar mass of 17g
3.47 * M(NH3) = 58.99g of NH3 in the cleaning agent

6 0

3 years ago

One of the postulates of bohr's atomic model of a moving electron is that angular momentum of a moving electron is quantized. Ex

oksano4ka [1.4K]

The angular momentum of an electron in the third Bohr orbit of a hydrogen atom is given by mvr=3h÷2π

<h3>What is momentum?</h3>

Momentum is defined as the amount of motion occurring in something that is moving, or the force that drives something forward to keep it moving.

Bohr never assumed stable electronic orbits with the electronic angular momentum quantized as

l=mvr = $\frac{nh}{2pi}$

Quantization of angular momentum means that the radius of the orbit and the energy will be quantized as well.

Bohr assumed that the discrete lines seen in the spectrum of the hydrogen atom were due to transitions of an electron from one allowed orbit/energy to another.

Learn more about momentum here:

https://brainly.in/question/38837394

#SPJ1

5 0

2 years ago

A compound contains only c, h, and n. it is 58.51% c and 7.37% h by mass. helium effuses through a porous frit 3.20 times as fas

Anika [276]

Let us assume that there are 100 grams of substance present. The masses of the constituents will be:

C - 58.51 g
H - 7.37 g
N - 100 - 58.51 - 7.37 = 34.12 g

Next, we determine the moles of each substance by dividing by the atomic masses:

C - 58.51/12 = 4.88
H - 7.37/1 = 7.37
N - 34.12/14 = 2.44

Dividing all of the moles by the lowest number of moles, which is 2.44 of nitrogen, we get the ratio:

C - 2
H - 3
N - 1

The empircal formula becomes C₂H₃N

Next, we apply Graham's Law of diffusion, which mathematically is:

v₁/v₂ = √M₂ / √M₁

Let species 1 be helium, meaning v₁/v₂ = 3.2 and M₁ = 4

3.2 = √M₂ / √4

M₂ = 40.96

The mass of the empircal formula was:
12 * 2 + 1 * 3 + 14 = 41

The empircal formula is the molecular formula as their masses are approximately the same. This compound is C₂H₃N

4 0

3 years ago

Trichloroethylene, a widely used degreasing solvent for machine parts, is produced in a two-step reaction sequence. Ethylene is

solmaris [256]

Answer:

ΔH°C2H2Cl4(l) = -333,36 kJ/mol

ΔH°r₂ = -35,14 kJ/mol

Explanation:

The ΔH°r of the first reaction is:

ΔH°r = -385,76 kJ/mol = (ΔH°C2H2Cl4(l) + ΔH°H2(g)) - (ΔH°C2H4(g) + 2ΔHCl2 (g))

ΔH°H2(g) = 0 kJ/mol

ΔH°C2H4(g) = 52,4 kJ/mol

Δ°HCl2 (g) = 0 kJ/mol

Replacing:

ΔH°C2H2Cl4(l) = -385,76 kJ/mol + 52,4 kJ/mol = <em>-333,36 kJ/mol</em>

The standard heat of the second reaction is:

ΔH°r₂ = ΔH°C2HCl3(l) + ΔH°HCl(g) - ΔH°C2H2Cl4(l)

Where:

ΔH°C2HCl3(l) = -276,2 kJ/mol; ΔH°HCl(g) = -92,3 kJ/mol; ΔH°C2H2Cl4(l) = -333,36 kJ/mol

Replacing:

ΔH°r₂ = -276,2 kJ/mol -92,3 kJ/mol + 333,36 kJ/mol

I hope it helps!

4 0

3 years ago

What happens during evaporation? A liquid changes to a gas. A liquid changes to a solid. A gas changes to a liquid. A solid chan

Valentin [98]

Answer:

A liquid changes to gas

Explanation:

"Evaporation is the process by which water changes from a liquid to a gas or vapor. Evaporation is the primary pathway that water moves from the liquid state back into the water cycle as atmospheric water vapor."

4 0

2 years ago