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
babunello [35]
3 years ago
8

The freezing point of a solution prepared by dissolving 150 × 10–3 g of caffeine in 10.0 g of camphor is lower by 3.07°C than th

at of pure camphor (Kf = 39.7°C/m). What is the molar mass of caffeine?
Physics
1 answer:
Finger [1]3 years ago
6 0

Answer:

Molar Mass=193.9738 g/mol

Molar Mass≅194g/mol

Explanation:

Consider the formula:

m=ΔT/K_{f}

where:

ΔT is freezing point depression

K_{f} is freezing point depression constant

m is the morality=(moles of solute/kg of solvent)

Now:

m=\frac{3.07}{39.7}

m=0.07733 moles of solute/kg of solvent

Now:

0.07733 (moles of solute/kg of solvent) *0.010 kg of solvent

7.733*10^{-4} moles of solute(Caffeine)

Molar mass = Mass of solute/moles of solute

Molar Mass=\frac{150*10^-3}{7.733*10^{-4} }

Molar Mass=193.9738 g/mol

Molar Mass≅194g/mol

You might be interested in
A uniform electric field exists in the region between two oppositely charged plane parallel plates. A proton is released from re
valentinak56 [21]

Answer:

a) 17.33 V/m

b) 6308 m/s

Explanation:

We start by using equation of motion

s = ut + 1/2at², where

s = 1.2 cm = 0.012 m

u = 0 m/s

t = 3.8*10^-6 s, so that

0.012 = 0 * 3.8*10^-6 + 0.5 * a * (3.8*10^-6)²

0.012 = 0.5 * a * 1.444*10^-11

a = 0.012 / 7.22*10^-12

a = 1.66*10^9 m/s²

If we assume the electric field to be E, and we know that F =qE. Also, from Newton's law, we have F = ma. So that, ma = qE, and E = ma/q, where

E = electric field

m = mass of proton

a = acceleration

q = charge of proton

E = (1.67*10^-27 * 1.66*10^9) / 1.6*10^-19

E = 2.77*10^-18 / 1.6*10^-19

E = 17.33 V/m

Final speed of the proton can be gotten by using

v = u + at

v = 0 + 1.66*10^9 * 3.8*10^-6

v = 6308 m/s

5 0
3 years ago
Please helppp....What are 5 examples of real science
valentina_108 [34]

Answer:

dynamics

kinematics

fluid mechanisms

earth science and

physics

8 0
3 years ago
What is the name of the plate to the west and directly adjacent to the plate on which Chile is located?
Ksenya-84 [330]
<h2>Answer: Nazca plate</h2>

Explanation:

The Nazca plate is an oceanic tectonic plate that is found in the Pacific Ocean off the west coast of South America, specifically in front of the north and central coast of Chile and the entire coastline of Peru, Ecuador and Colombia. This plate is in constant motion, which causes it to sink under the South American (phenomenon known as subduction).

It is mainly because of this subduction process that this region has a lot of seismic activity. Another important aspect is that thanks to these movements, the Andes mountain range and the Peruvian-Chilean fossa originated.

6 0
3 years ago
Which of the following would have an effect on an object's mass?
ICE Princess25 [194]
None of the above

mass is measurement of how much stuff in inside something.
if you freeze or heat an object, you merely change the state of the object. the mass is conserved.
if you change the elevation, nothing happens to the mass. the stuff will not leave the object.
so it is None of the above


8 0
3 years ago
In no more than five simple statements, use the kinetic theory to explain why an iron bar expands when it is heated.
lozanna [386]

Answer:

Iron expands because heating increases the space between the molecules

Explanation:

According to the kinetic molecular theory, all matter is composed of atoms and molecules which are in constant motion.

When a substance is heated, molecules of the substance begin to vibrate faster. This faster vibration leads to increased space between the molecules (expansion) . The kind of motion motion and degree of spacing of the molecules determine the state of matter in which the substance is found.

Hence, when an iron bar is heated, it expands due to increased motion of its molecules leading to spaces between them.

7 0
4 years ago
Other questions:
  • Two charged particles move in the same direction with respect to the same magnetic field. particle 1 travels two times faster th
    7·1 answer
  • If you put a pencil in a cup of water, it looks as if it is bent and larger in the water. This is because waves
    8·2 answers
  • The unit for measuring electric power is the <br> A. ampere.<br> B. volt.<br> C. ohm.<br> D. watt.
    14·1 answer
  • A convex lens with focal length 9 cm forms an image of an object placed 21 cm to the left of the lens. what is the distance to t
    8·1 answer
  • An incident ray parallel to the axis and one through the focal point reflect and converge at the image.
    7·2 answers
  • Although sunlight is unpolarized, the light that reflects from smooth surfaces may be partially polarized in the direction paral
    6·1 answer
  • In a solid, the particles vibrate vibrate on the spot. They do not move around. In a liquid, particles are together. They are to
    11·1 answer
  • What property of sound does a decibel measure
    13·2 answers
  • You perform nine (identical) measurements of the acceleration of gravity (units of m/s2): 10.1,9.87, 9.76, 9.91, 9.75, 9.88, 9.6
    15·1 answer
  • A softball needs to hit a bucket 43. 0 m away on flat ground. if it is aimed at 72. 0, what must its inital velocity be?
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!