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4 years ago

Which statement about the discovery of electrons is true?

Chemistry

1 answer:

Softa [21]4 years ago

8 0

Answer:

The true statement about the discovery of electrons is :

C. Electrons were discovered in a vacuum tube

Explanation:

In 1870, Sir William Crookes developed the first cathode ray tube which have high vacuum inside.

These rays moved the paddled wheel when placed in their path.This means these rays have some momentum.

When the magnetic field was applied to the cathode rays they showed deflection. This means these cathode rays must have some charge because only charged particles can show deflection when place in magnetic field.

Later is was found by J.J Thomson that these are negatively charged.

How ?

We Know that like charges repel each other and unlike charges attract each other. This means if a particle has negative charge then it will attract the positive charge.

J.J Thomson studied these cathode ray tubes and found that these rays repels the negative charge particles .Hence these rays must be negatively charged.

He called these tiny Particle "electron"

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Gasone provides the energy that powers many car engines. In an engine, gasoline and oxygen are mixed together and burned, creati

Leya [2.2K]

Answer:

In the forward direction and releases carbondioxide gas from backside.

Explanation:

In the forward direction and the carbondioxide gas which is a waste material is removed from the engine at the back. The chemical energy of fuel is converted into mechanical energy with the help of engine which able the car to move in the forward direction so engine is the key component that is responsible for the movement of car.

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3 years ago

Read 2 more answers

Can you find a salmander in the desert or rainforest?

vodka [1.7K]

You can find it in rainforest because they like damp places.

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3 years ago

If 20.0g of CO2 and 4.4g of CO2

Ksivusya [100]

The given question is incorrect. The correct question is as follows.

If 20.0 g of $O_{2}$ and 4.4 g of $CO_{2}$ are placed in a 5.00 L container at $21^{o}C$ , what is the pressure of this mixture of gases?

Explanation:

As we know that number of moles equal to the mass of substance divided by its molar mass.

Mathematically, No. of moles = $\frac{\text{mass}}{\text{molar mass}}$

Hence, we will calculate the moles of oxygen as follows.

No. of moles = $\frac{\text{mass}}{\text{molar mass}}$

Moles of $O_{2}$ = $\frac{20.0 g}{32 g/mol}$

= 0.625 moles

Now, moles of $CO_{2} = \frac{4.4 g}{44 g/mol}$

= 0.1 moles

Therefore, total number of moles present are as follows.

Total moles = moles of $O_{2}$ + moles of $CO_{2}$

= 0.625 + 0.1

= 0.725 moles

And, total temperature will be:

T = (21 + 273) K = 294 K

According to ideal gas equation,

PV = nRT

Now, putting the given values into the above formula as follows.

P = $\frac{nRT}{V}$

= $\frac{0.725 mol \times 0.08206 Latm/mol K \times 294 K}{5.00 L}$

= $\frac{17.491089}{5}$ atm

= 3.498 atm

or, = 3.50 atm (approx)

Therefore, we can conclude that the pressure of this mixture of gases is 3.50 atm.

4 0

3 years ago

What is the madd in grams of 0.40 moles of sodium borohydride, NaBH4

Orlov [11]

Answer:

Mass = 15.1 g

Explanation:

Given data:

Number of moles of NaBH₄ = 0.40 mol

Mass in gram = ?

Solution:

Formula:

Mass = number of moles × molar mass

Molar mass of NaBH₄ = 37.83 g/mol

By putting values,

Mass = 0.40 mol × 37.83 g/mol

Mass = 15.1 g

3 0

3 years ago

Argon atom can exist freely in nature, why

lana [24]

Answer:

Argon can exist freely in nature because it has a full octet of electrons the way its found in the nature is the same way its found in periodic table of element in vast amouts of stabilization.

7 0

3 years ago