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MrMuchimi
3 years ago
6

Prepare 250 cm3 2M NAOH: molar mass M = 40g/mol. calculate substance mass​

Engineering
1 answer:
charle [14.2K]3 years ago
6 0

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.

Molarity=\frac{n\times 1000}{V_s}

where,

n = moles of solute

V_s = volume of solution in ml  = 250 ml   (1cm^3=1ml)

moles of NaOH = \frac{\text {given mass}}{\text {Molar mass}}=\frac{xg}{40g/mol}

Now put all the given values in the formula of molality, we get

2=\frac{x\times 1000}{40\times 250}

x=20g

Therefore, the mass of the substance is 20 g

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Norma-Jean [14]

Answer:

The inductance of the inductor is 0.051H

Explanation:

From Ohm's law;

  V = IR .................. 1

The inductor has its internal resistance referred to as the inductive reactance, X_{L}, which is the resistance to the flow of current through the inductor.

From equation 1;

V = IX_{L}

X_{L} = \frac{V}{I} ................ 2

Given that; V = 240V, f = 50Hz, \pi = \frac{22}{7}, I = 15A, so that;

From equation 2,

X_{L}= \frac{240}{15}

    = 16Ω

To determine the inductance of the inductor,

X_{L} = 2\pifL

L = \frac{X_{L} }{2 \pi f}

  = \frac{16}{2*\frac{22}{7}*50 }

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The inductance of the inductor is 0.051H.

4 0
4 years ago
Coulomb's Law Two point charges experience an attractive force of 10.8 N when they are separated by 2.4 m. VWhat force in newton
SashulF [63]

Answer:

The force between the charges when the separation decreases to 0.7 meters equals 126.955 Newtons

Explanation:

We know that for two point charges of magnitude q_{1},q_{2} the magnitude of force between them is given by

F=\frac{k_{e}q_{1}\cdot q_{2}}{r^{2}}

where

k_{e} is constant

r is the separation between the charges

Initially when the charges are separated by 2.4 meters the force can be calculated as

F_{1}=\frac{k_{e}\cdot q_{1}q_{2}}{2.4^{2}}\\\\10.8=\frac{k_{e}\cdot q_{1}q_{2}}{2.4^{2}}\\\\\therefore k_{e}\cdot q_{1}q_{2}=10.8\times 2.4^{2}=62.208

Now when the separation is reduced to 0.7 meters the force is similarly calculated as

F_{2}=\frac{k_{e}\cdot q_{1}q_{2}}{0.7^{2}}

Applying value of the constant we get

F_{1}=\frac{62.208}{0.7^{2}}

Thus F_{2}=126.955Newtons

5 0
3 years ago
Draw a flowchart to represent the logic of a program that allows the user to enter values for the current year and the user’s bi
Digiron [165]

Answer:

Please, see the attachment.

Explanation:

First, we have to create two input boxes that allows the user to write the current year in one of them and his/her birth year in the another one. Also, we have to create a label that will show the result of the desired variable. We can write a message "Your age is:" and it will be attached to the result.

For the algorithm, let's call the variables as follows:

CY = Current Year

BY = Birth Year

X = Age of user

When the user inserts the current year and his/her birth year, the program will do the following operation:

X = CY - BY; this operation will give us the age of the user

After this the user will see something like "Your age is:" X.

3 0
3 years ago
forty gal/min of a hydrocarbon fuel having a spesific gravity of 0.91 flow into a tank truck with load limit of 40,000 lb of fue
Zina [86]

Answer: 131.75minutes

Explanation:

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= 0.91 × 8.34lb/gallon

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Then, the volume that's required to fill the tank will be:

= Load limit/Density of fluid

= 40000/7.59

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Now, the time taken will be:

= V/F

= 5270.1/40

= 131.75min

It'll take 131.75 minutes to fill the tank in the truck.

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k0ka [10]

Answer:

  • B. Precipitation require the diffusional activation energy plus an additional energy to form the precipitate.

Explanation:

Precipitation is the creation of a solid from a solution. When the reaction occurs in a liquid solution, the solid formed is called the precipitate.

The formation of a precipitate indicates the occurrence of a chemical reaction.

Precipitation of carbide requires alot of energy which the diffusion activational energy alone cannot achieve and this was calculated to be 225.6 kJ/mol.

3 0
4 years ago
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