What is a layer of solid of the solid earth<br>

How many molecules of Ca are found in a sample with 0.2 mols?

DochEvi [55]

Answer:

$\boxed{1.2 \times 10^{23}\text{ atoms}}$

Explanation:

6.023 × 10²³ atoms of Ca are in 1 mol of Ca

$\text{No. of atoms} = \text{0.2 mol} \times \dfrac{6.023 \times 10^{23}\text{atoms }}{\text{1 mol }} = \mathbf{1.2 \times 10^{23}} \textbf{ atoms}}\\\\\text{There are }\boxed{\mathbf{1.2 \times 10^{23}} \textbf{ atoms}} \text{ atoms in 0.20 mol of Ca}$

6 0

3 years ago

There are two different compounds of sulfur and fluorine.

olga nikolaevna [1]

What's your question......................

5 0

4 years ago

Rank the following solutions in order of increasing acidity (least acidic to most acidic): I: [H3O+] = 1x10−5 II: [OH−] = 1x10−1

kozerog [31]

Answer: option C) II < III < I

i.e [OH−] < [H3O+] < I

Explanation:

First, obtain the pH value of I and II, then compare both with III.

For I

Recall that pH = -log (H+)

So pH3O = -log (H3O+)

= - log (1x10−5)

= 4

For II

pOH = - log(OH-)

= - log(1x10−10)

= 9

For III

pH = 6

Since, pH range from 1 to 14, with values below 7 to be acidic, 7 to be neutral, above 7 to be alkaline: then, 9 < 6 < 4

Thus, the following solutions from least acidic to most acidic is II < III < I

6 0

3 years ago

Two chemist are trying to determine if their water sample is a mixture or pure substance. In their investigation they first filt

Effectus [21]

The correct answer is option B. Dirty water is a mixture of solid particles and liquid. It is both a mixture and pure substance.

The dirty water sample has both gravel and liquid water in it. After filtration the gravel is removed so the water sample looks clearer than before filtration. Liquid water is a pure substance because it is a compound that is made up of elements hydrogen and oxygen. Now the gravel is only physically combined with the liquid water, thus giving the water sample properties of a mixture. And like any mixture, gravel is physically separated through filtration from the liquid water.

Thus the water sample of the chemists is both a mixture and pure substance.

8 0

4 years ago

(1)List three things you know about<br> an atom? (2) What is matter created of?

kicyunya [14]

Answer:

Atoms consist of three basic particles: protons, electrons, and neutrons. The nucleus (center) of the atom contains the protons (positively charged) and the neutrons (no charge). The outermost regions of the atom are called electron shells and contain the electrons (negatively charged).

Explanation:

8 0

3 years ago

What is a layer of solid of the solid earth​

What is a layer of solid of the solid earth