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
yKpoI14uk [10]
3 years ago
13

How many moles of MgCl2 are there in 305 g of the compound? Answer and units

Physics
1 answer:
Alona [7]3 years ago
8 0
Wrong subject.  Expect that to be in chemistry.

Here it is:

One mole of a compound/element contains the weight in grams equal to the sum of the molecular mass.
For MgCL2,
Mg=24.30
Cl=35.45
so the molecular mass = 24.30+2*35.45=24.30+70.9=95.20 (approximately).
=>
One mole of MgCl2 weighs 95.20 g.

305 g of MgCl2 = 305/95.20 = 3.20 moles, to 3 significant figures

Edit: improved accuracy of atomic masses.
You might be interested in
Allen and Jason are chucking a speaker around. On one particular throw, Allen throws the speaker, which is playing a pure tone o
Sholpan [36]

Answer:

Explanation:

We shall apply Doppler's effect of sound .

speaker is the source , Jason is the observer . Source is moving at 10 m /s , observer is moving at  6 m/s .

apparent frequency = f_o\times\frac{V+v_o}{ V-v_s}

V is velocity of sound , v₀ is velocity of observer and v_s is velocity of source and f_o is real frequency of source .

Here V = 340 m/s , v₀ is 6 m/s , v_s is 10 m/s . f_o = f

apparent frequency =  f\times \frac{340+6}{340-10}

= f\times \frac{346}{330}

So m = 346 , n = 330 .

8 0
3 years ago
Which of the following is not a reason why plants need water? *
solong [7]

Answer:

C

Explanation:

the plant cools itself down by allowing water to evaporate from their leaves so it doesn't need water to cool down

5 0
3 years ago
Refrigerant-134a enters a compressor at 180 kPa as a saturated vapor with a flow rate of 0.35 m3/min and leaves at 900 kPa. The
Alexus [3.1K]

Answer:

52.5°C

Explanation:

The final enthalpy is determined from energy balance where initial enthalpy and specific volume are obtained from A-12 for the given pressure and state

mh1 + W = mh2

h2 = h1 + W/m

h1 + Wα1/V1

242.9 kJ/kg + 2.35.0.11049kJ/ 0.35/60kg

=287.4 kJ/kg

From the final enthalpy and pressure the final temperature is obtained A-13 using interpolation

i.e T2 = T1 + T2 -T1/h2 -h1(h2 - h1)

= 50°C + 60 - 50/295.15 - 284.79

(287.4 - 284.79)°C

= 52.5°C

7 0
3 years ago
Geologists use tools other than the law of superposition to help them with relative dating. Which statements describe those tool
White raven [17]

Answer: Cross-cutting features are always younger than the surrounding rock.

When material erodes before sediment is deposited on it, a geologic gap results.

Explanation:

The options include:

1. An unconformity is created when lava pours out on Earth’s surface.

2. Faults are the result of volcanic activity.

3. Intrusions and extrusions are sedimentary formations.

4. Cross-cutting features are always younger than the surrounding rock.

5. When material erodes before sediment is deposited on it, a geologic gap results.

The law of superposition simply states that when there is a layers of rocks, we would see that the younger layers will lie and be on top of the layers that are older.

Other tools that can help scientist with relative dating are:

• Cross-cutting features are always younger than the surrounding rock.

• When material erodes before sediment is deposited on it, a geologic gap results.

6 0
3 years ago
Describe the difference between a conductor and an insulator in terms of thermal energy transfer and provide an example of each.
Nikitich [7]

The difference between conductors and insulators is because of electronic structure of atoms and molecules.

 

Anywhere we have free electrons, we have a hard conductor where free electrons help in conduction.

 

In electrolytes, charged Ions do conduction.

 

Dielectrics (or insulators) don't have free electrons current.

 

Free electrons mean, the electrons that are not related with a specific atom, they are allowed to move nearby the crystal lattice.

4 0
3 years ago
Other questions:
  • A rocket takes off from Earth. It travels 825km in 75 seconds. What is the
    10·1 answer
  • If an airplane is flying at 300 km/h to the east and is facing a headwind of 18.0 km/h, what is the airplane's final velocity?
    14·1 answer
  • I need some advice I have two girlfriends as of now.
    5·2 answers
  • A horizontal spring with spring constant 210 Nm is compressed by 20 cm and then used to launch a 250 g box across the floor. The
    11·1 answer
  • How much power is needed to lift the 200-N object to a height of 10 m in 4 s?
    9·1 answer
  • A football player threw a ball upward at an angle or 24 degrees with the horizontal with A velocity of 18 m/s. What are the vert
    13·1 answer
  • Are the statements of the Flat Earth Society an example of science or pseudoscience?
    13·2 answers
  • An object of 4 cm length is placed at a distance of 18 cm in front of a convex mirror of radius of curvature 30 cm. Find the pos
    7·1 answer
  • g What is the separation between their paths in meters when they hit a target after traversing a semicircle
    14·1 answer
  • Please Help Me!!!
    7·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!