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3 years ago

How are rare earth elements important to our technological world?

1 answer:

4 0

Rare earth elements are a series of chemical elements found in the earth's crust and are vital to many of the modern technologies in the world such as computers and networks, advanced transportation and consumer electronics. They help fuel economic growth, maintain high living standards and even save lives. Examples include:

Scandium. Used in television and fluorescent lamps.

Yttrium. Used in cancer treatment drugs, superconductors and camera lenses

Lanthanum. Used to make special optical glasses, telescope lenses and also in petroleum refining.

Neodymium. Used in making some of the strongest permanent magnets, found in most modern vehicles and aircraft.

You might be interested in

What are some of the benefits of using measurements to find density? Provide 2 each. What are some of the challenges of using me

stellarik [79]

Some of the benefits of using measurements to find density include the following:

It is easy and doesn't require experiments.
The volume of both light and dense molecule can be gotten.

Some of the challenges of using measurements to find density include the following:

Inconsistency in the grind setting
Temperature changes not taken into account.

<h3>What is Density?</h3>

This is defined as the mass per unit volume of a substance or te degree of compactness of a substance and can be gotten with the use of measurements or experiments.

The measurement doesn't take the temperature changes into consideration which will lead to the result being most likely incorrect. It is also advantageous because less time is used thereby making it easier.

Read more about Density here brainly.com/question/406690

#SPJ1

7 0

2 years ago

Fe2O3 + CO --> Fe + CO2

satela [25.4K]

Answer:

The answer to your question is

1.-Fe₂O₃

2.- 280 g

3.- 330 g

Explanation:

Data

mass of CO = 224 g

mass of Fe₂O₃ = 400 g

mass of Fe = ?

mass of CO₂

Balanced chemical reaction

Fe₂O₃ + 3CO ⇒ 2Fe + 3CO₂

1.- Calculate the molar mass of Fe₂O₃ and CO

Fe₂O₃ = (56 x 2) + (16 x 3) = 160 g

CO = 12 + 16 = 28 g

2.- Calculate the proportions

theoretical proportion Fe₂O₃ /3CO = 160/84 = 1.90

experimental proportion Fe₂O₃ / CO = 400/224 = 1.78

As the experimental proportion is lower than the theoretical, we conclude that the Fe₂O₃ is the limiting reactant.

3.- 160 g of Fe₂O₃ --------------- 2(56) g of Fe

400 g of Fe₂O₃ --------------- x

x = (400 x 112) / 160

x = 280 g of Fe

4.- 160 g of Fe₂O₃ --------------- 3(44) g of CO₂

400 g of Fe₂O₃ -------------- x

x = (400 x 132)/160

x = 330 gr

3 0

3 years ago

The amide formed in the reaction of 3-ethylbenzoic acid and dimethylamine is

crimeas [40]

Answer: -

3-Ethyl-N,N-dimethylbenzamide.

Explanation: -

In the first step the nitrogen lone pair attacks the carbonyl carbon.

Then a OH becomes water molecule by protonation and leaves.

Final step involves proton loss to form amide.

4 0

3 years ago

an element is a mixture of two isotopes. one isotope has an atomic mass of 34.96885 amu and has an abundance of 75.53%. The othe

DochEvi [55]

Answer:

35.4575 amu

Explanation:

We use the relative abundance of each of the isotopes.

Let the isotopes be A and B.

Since A is having an abundance of 75.53, the abundance of B would be 100 - 75.53 = 24.47%

The average atomic mass is calculated as follows;

(75.53/100 * 34.96885) + (24.47/100 * 36.96590) = 26.4119 + 9.0456 = 35.4575 amu

7 0

4 years ago

160 mL of a 37.5 % (m/v) LiNO3 solution

Alex17521 [72]

Answer:

60g of LiNO3 are required

Explanation:

<em>Calculate the amount of solute, in grams or milliliters, to prepare...</em>

<em />

The percentage mass/volume %(m/v) is defined as the mass in grams of the solute in 100mL of solution

To solve this question we must know that in a 37.5% (m/v) of LiNO3 you have 37.5g of LiNO3 in 100mL of solution.

Thus, to prepare 160mL are required:

160mL * (37.5g / 100mL) =

<h3>60g of LiNO3 are required</h3>

8 0

3 years ago