1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
julsineya [31]
3 years ago
12

Machines are never 100 percent efficient because some work is used to overcome friction and inertia. True False

Chemistry
2 answers:
ElenaW [278]3 years ago
7 0
False,
machines constantly mess up
Y_Kistochka [10]3 years ago
3 0
This is wrong because machines can make mistakes that why we fix it
You might be interested in
Is this right??? If not gimme da right answer plz
NemiM [27]

Answer:

yeah

Explanation:

well, probably. they kicked me out of math class because I put a live chicken in the classroom and it pooped everywhere, so I had to clean it up and bring it back where I found it (which is the side of the road.)

3 0
3 years ago
Read 2 more answers
Identify the intermolecular attractions for dimethyl ether and for ethyl alcohol. Which molecule is expected to be more soluble
zheka24 [161]

Answer:

See explanation

Explanation:

All molecules possess the London dispersion forces. However London dispersion forces is the only kind of intermolecular interaction that exists in nonpolar substances.

So, the only kind of intermolecular interaction that exists in dimethyl ether is London dispersion forces.

As for ethyl alcohol, the molecule is polar due to the presence of polar O-H bond. In addition to London dispersion forces, dipole-dipole interactions and specifically hydrogen bonding also occurs between the molecules.

Because ethyl alcohol is polar, it is more soluble in water than dimethyl ether.

3 0
3 years ago
While heating up a 25 gram sample of concrete (specific heat = 0.210-cal/g°C), your initial tempărature is room temperature (25°
Lana71 [14]

Answer:

Final temperature  = 83.1 °C

Explanation:

Given data:

Mass of concrete = 25 g

Specific heat capacity = 0.210 cal/g. °C

Initial temperature = 25°C

Calories gain = 305 cal

Final temperature = ?

Solution:

Q = m. c. ΔT

Q = amount of heat absorbed or released

m = mass of given substance

c = specific heat capacity of substance

ΔT = change in temperature

ΔT = T2 - T1

305 cal = 25 g ×0.210 cal/g.°C × T2 -  25°C

305 cal = 5.25cal/°C × T2 -  25°C

305 cal / 5.25cal/°C = T2 -  25°C

58.1 °C = T2 -  25°C

T2 = 58.1 °C + 25°C

T2 = 83.1 °C

7 0
2 years ago
Se construye una pila galvánica con una barra de cobre sumergida en una disolución 1M de cationes Fe+2 y una barra de plata sume
pashok25 [27]

Answer:

El potencial celular estándar, E_{cell} is +0.46 V

Explanation:

Las reacciones de media célula son;

Media reacción del ánodo Cu²⁺ + 2e⁻ ↔ Cu, E ° = 0.34 V

Media reacción catódica 2Ag + 2e⁻ ⁻ 2Ag, E ° = 0.80 V

Sin embargo tenemos para hierro Fe²⁺ + 2e⁻ ↔ Fe, E ° -0.44 V

y Fe³⁺ + e⁻ ↔ Fe²⁺, E ° = 0.77 V

 que es más alta que la del cobre presente, por lo tanto, el cobre se oxidará en el ánodo

Por lo tanto, en el ánodo, tendremos

Cu → Cu²⁺ + 2e⁻ (E ° = -0.34 V)

En el cátodo

2Ag + 2e⁻ → 2Ag (E ° = 0.80 V)

E_{cell} = E_c + E_a = -0.34 + 0.8 = +0.46 \, V

El potencial celular estándar, E_{cell} = +0.46 V

4 0
3 years ago
When a hydrogen atom makes the transition from the second excited state to the ground state (at -13.6 eV) the energy of the phot
viktelen [127]

Answer : The energy of the photon emitted is, -12.1 eV

Explanation :

First we have to calculate the 'n^{th}' orbit of hydrogen atom.

Formula used :

E_n=-13.6\times \frac{Z^2}{n^2}ev

where,

E_n = energy of n^{th} orbit

n = number of orbit

Z = atomic number  of hydrogen atom = 1

Energy of n = 1 in an hydrogen atom:

E_1=-13.6\times \frac{1^2}{1^2}eV=-13.6eV

Energy of n = 2 in an hydrogen atom:

E_3=-13.6\times \frac{1^2}{3^2}eV=-1.51eV

Energy change transition from n = 1 to n = 3 occurs.

Let energy change be E.

E=E_-E_3=(-13.6eV)-(-1.51eV)=-12.1eV

The negative sign indicates that energy of the photon emitted.

Thus, the energy of the photon emitted is, -12.1 eV

3 0
3 years ago
Other questions:
  • Give the product of the reaction of excess benzene (2 equivalents) with dichloromethane and alcl3.
    6·1 answer
  • EASY 8TH GRADE SCIENCE PLEASE HELP
    8·1 answer
  • When standardizing an iodine solution, 30.37 ml of the solution was required to completely oxidize 10.00 ml of a 5 mg/ml solutio
    11·1 answer
  • 1.
    13·1 answer
  • _______________ galaxies range in shape from almost perfect spheres to flattened globes with the light brightest in the center a
    5·2 answers
  • A cylinder of Krypton has contains 17 L of Ar at 22.8 atm and 112 degrees celsisus. How many moles are in the cylinder?​
    11·1 answer
  • When a chemical reaction occurs, what happens to the atoms of the two substances?
    14·2 answers
  • Why should you label your plates on the bottom instead on the lid?
    14·1 answer
  • 10. When a substance is analyzed using an electron microscope, it is found
    13·1 answer
  • Substance
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!