How may sun are in earth

Is quartz(SiO2) a substance or mixture?

Illusion [34]

Quartz is a substance because the material has uniform properties throughout and is held together via chemical bonds.

8 0

3 years ago

1. How much 6.0 M HNO3 is needed to neutralize 39 mL of 2.0 M KOH?

quester [9]

Answer:

For 2. the answer is 15.0 mL

For other examples, you can solve by exact way as I have solved the 2nd example.

I have writen down all the balanced chemical reaction equation for examples 1, 3, 4, 5 for you. ( picture 2 )

Explanation:

Please see the step-by-step solution in the picture attached below.(picture 1)

Hope this answer can help you. Have a nice day!

6 0

3 years ago

How many grams of material is lost in the aqueous phase if two extractions are carried out on 100 mL of a 5% (m/v) aqueous solut

san4es73 [151]

Answer:

4.94g of material

Explanation:

Partition coefficient (Kp) of a substance is defined as the ratio between concentration of organic solution and aqueous solution, that is:

Kp = 8 = Concentration in Ethyl acetate / Concentration in water

100mL of a 5% solution contains 5g of material in 100mL of water. Thus:

8 = X / 100mL / (5g-X) / 100mL

Where X is the amount of material in grams that comes to the organic phase.

8 = X / 100mL / (5g-X) / 100mL

8 = 100X / (500-100X)

4000 - 800X = 100X

4000 = 900X

4.44g = X

Thus, in the first extraction you will lost 4.44g of material from the aqueous phase.

And will remain 5g-4.44g = 0.56g.

In the second extraction:

8 = X / 100mL / (0.56g-X) / 100mL

8 = 100X / (56-100X)

448 - 800X = 100X

448 = 900X

0.50g = X

In the second extraction, you will extract 0.50g of material

Thus, after the two extraction you will lost:

4.44g + 0.50g = 4.94g of material

6 0

2 years ago

What is the net charge of the ionic compound calcium fluoride

yKpoI14uk [10]

Answer:

The net charge of the ionic compound calcium fluoride is zero (0).

Explanation:

Ionic compounds, such as covalent ones, have zero net charge; this is, they are neutral.

Substances with net positive charge are cations and substances with net negative charge are anions.

The charges in the ionic compound calcium flouride are distributed in this way:

Compound formula: CaF₂

Calcium charge: Ca²⁺: this is, each calcium ion has a 2 positive charge

Fluoride charge: F⁻: each fluoride ion has a 1 negative charge.

Then, the net charge is: 1 × (2+) + 2 × (1-) = +2 - 2 = 0.

So, a two positve charge, from one calcium ion, is equal to two negative charges, from two fluoride tions, yielding a zero net charge.

8 0

3 years ago

A substance made of both metal and nonmetal atoms ?

Nat2105 [25]

A metalloid is a metal and a nonmetal

6 0

3 years ago