Answer: The mass of the substance is 20 g
Explanation:
Molarity of a solution is defined as the number of moles of solute dissolved per liter of the solution.
[tex]Molarity=\frac{n\times 1000}{V_s}[/tex]
where,
n = moles of solute
[tex]V_s[/tex] = volume of solution in ml = 250 ml [tex](1cm^3=1ml)[/tex]
moles of [tex]NaOH[/tex] = [tex]\frac{\text {given mass}}{\text {Molar mass}}=\frac{xg}{40g/mol}[/tex]
Now put all the given values in the formula of molality, we get
[tex]2=\frac{x\times 1000}{40\times 250}[/tex]
[tex]x=20g[/tex]
Therefore, the mass of the substance is 20 g
Vacancy diffusion statement refer to that a mechanism that
atom at lattice traveled to a vacant latblèe
• True
• False
Answer:
true
Explanation:
determine the steady state temperature distribution between two concentric spheres with radii 1 and 4
Answer:
Hence, the steady state temperature distribution between concentric spheres with radii 1 and 4 is:
u = [tex]\frac{C1}{r }[/tex] + C2
u = [tex]\frac{\frac{-320}{3} }{r}[/tex] + [tex]\frac{320}{3}[/tex]
Explanation:
Solution:
Note: This question is incomplete and lacks necessary data to solve this question. But I have found a similar question and will try to solve it.
This question has this following part missing:
"If the temperature of the outer sphere is maintained at 80 degrees and the inner sphere at 0 degrees.
Now, this question is complete.
Let's find out the steady state temperature distribution.
As, we know the spherical symmetric heat equation:
[tex]\frac{du}{dt}[/tex] = [tex]\frac{k}{r^{2} }[/tex] [tex]\frac{D}{Dr}[/tex] ([tex]r^{2}[/tex] [tex]\frac{Du}{Dr}[/tex])
Where, small (d) represents the partial differentiation and Capital D represents simple derivative.
And the ordinary differential equation (ODE) for steady state temperature distribution is:
[tex]\frac{k}{r^{2} }[/tex] [tex]\frac{D}{Dr}[/tex]([tex]r^{2}[/tex] [tex]\frac{Du}{Dr}[/tex]) = 0
So it can be said that:
[tex]r^{2}[/tex] [tex]\frac{Du}{Dr}[/tex]
Consequently,
[tex]\frac{Du}{Dr}[/tex] = [tex]\frac{C1}{r^{2} }[/tex]
Taking derivative of the above equation we get:
u = -[tex]\frac{C1}{r }[/tex] + C2
Solution of the ordinary differential equation
u = [tex]\frac{C1}{r }[/tex] + C2 (Consuming the negative sign into C1 constant)
As, it is given in our question that our boundary conditions are: 1 and 4
So,
Putting the boundary conditions into the variable (r) to find the constants we get:
u1 = [tex]\frac{C1}{1} }[/tex] + C2 = 0 (degrees)
u1 = C1 + C2 = 0 (degrees) equation (1)
Similarly,
u4 = [tex]\frac{C1}{4}[/tex] + C2 = 80 (degrees)
u4 = [tex]\frac{C1}{4}[/tex] + C2 = 80 (degrees) equation (2)
Solving for C1, we get:
Equation 1 - Equation 2
(C1 - C2 = 0) - ([tex]\frac{C1}{4}[/tex] + C2 = 80)
[tex]\frac{-3}{4}[/tex]C1 = 80
Solving for C1
C1 = -[tex]\frac{320}{3}[/tex]
With the help of value of C1, we get value of C2
Put the value of C1 in equation (1) to get value of C2
C1 + C2 = 0
-[tex]\frac{320}{3}[/tex] + C2 = 0
Solving for C2
C2 = [tex]\frac{320}{3}[/tex]
Hence, the steady state temperature distribution between concentric spheres with radii 1 and 4 is:
u = [tex]\frac{C1}{r }[/tex] + C2
Plugging in the values of C1 and C2
u = [tex]\frac{\frac{-320}{3} }{r}[/tex] + [tex]\frac{320}{3}[/tex]
7. What is the voltage across a 100 ohm circuit element that draws a current of 1 A?
Answer:
100 V
Explanation:
V = IR
100 x 1 = 100
100 volts
The voltage across a 100-ohm circuit element that draws a current of 1 A is 100 V.
What is electric current?Electric current is a term used to describe how much electricity flows across a circuit and how it flows in an electronic circuit. Amperes are used to measure it (A).
The more electricity flowing across the circuit, the higher the ampere value. The difference in electric potential between two places is known as voltage, electric potential difference, electric pressure, or electric tension.
Ampere is the SI unit of electric current and ohm is the SI unit of electric resistance.
The circuit element is 100 ohms
The current is 1 A.
Voltage = current (I) x resistance (r)
V = IR
100 x 1 = 100
100 volts
Therefore, the voltage across a 100-ohm circuit element is 100 volts.
To learn more about electric current, refer to the below link:
https://brainly.com/question/28019870
#SPJ2
Select the correct answer. What does a mechanical engineer do? O A. Designs buildings. OB. Designs roads. C. Designs consumer products. D. Designs machines,
Answer:
d
Explanation:
The ans is d, from the word mechanical dealing with machines
List 3 specific things you can do with a screw gun (not just screw in screws)
Answer:
Install drywall
insert wood panels
unscrew nails
Explanation:
IF YOUR VEHICLE BREAKS DOWN, YOU SHOULD?
Answer:
1. TURN ON YOUR HAZARD/EMERGENCY LIGHTS
Turn on your hazard lights to warn other drivers as soon as you sense something's wrong. Keep them on until help arrives, recommends the National Motorists Association (NMA).
2. SLOW DOWN AND PULL OFF THE ROAD
Aim for the right shoulder of the road. Consumer reports recommends that you pull over to a safe, flat location that is as far away from moving traffic as possible.
3. TURN YOUR WHEELS AWAY FROM THE ROAD AND PUT ON THE EMERGENCY BRAKE
The California Department of Motor Vehicles (DMV) recommends pulling your emergency brake, sometimes called the parking brake. If you have to park on a hill or slope, turn the car's wheels away from the road to help prevent the care from rolling into traffic, says the California DMV.
4. STAY IN YOUR VEHICLE
If you're on a highway or crowded road, the Insurance Information Institute (III) recommends that you avoid getting out of your vehicle to look at the damage or fix a mechanical problem. If you need to get out of the car, get your vehicle to a safe place and make sure the road around you is completely clear. If you're stopped on the right-hand side of the road, get out through the passenger-side door.
5. BE VISIBLE
Once you're safely out of the vehicle, prop up your hood to let other drivers know they should proceed with caution. This will alert other drivers that you're broken down, according to the NMA.
6. SET UP FLARES OR TRIANGLES
Place flares or triangles with reflectors behind your car to alert other drivers to the location where you've stopped, says the III.
7. CALL FOR HELP
Call or use an app to get a tow truck, mechanic or roadside assistance to come help. your insurance company or other provider who may be able to help. If you're in an emergency situation or are not sure who to contact, call 911 or the local police for help.
Hope this helps :)
(Giving Brainliest to 1st!)Which organelle acts as a temporary storage center, containing water, waste, and other products?
A. cell membrane
B. cytoplasm
C. vacuole
D. nucleus
The displacement of a certain object is described by y(t) = 23 sin 5t, where t is measured in seconds. Compute its period and its oscillation frequency in rad/sec and in hertz
Answer:
5 rad/sec
0.796 Hz
1.256 seconds
Explanation:
Y(t) = 23sin5t ----1
Y(t) = aSin(w)t----2
w = 5 rad/sec
Then we get the Oscillation frequency from the formula below
w = 2πf
We make f to be the subject of this formula
f = w/2π
f = 5/2*3.24
f = 5/6.28
f = 0.796Hz
From the calculated frequency, we get the period = 1/f
= 1/0.796
= 1.256 seconds