Answer: 6.3 x 10^-3 moles
Explanation:
Based on Avogadro's law:
1 mole of any substance has 6.02 x 10^23 atoms
So, 1 mole of potassium = 6.02 x 10^23 atoms
Z moles = 3.78 x 10^21 atoms
To get the value of Z, we cross multiply:
(3.78 x 10^21 atoms x 1mole) = (6.02 x 10^23 atoms x Z moles)
3.78 x 10^21 = (6.02 x 10^23 x Z)
Z = (3.78 x 10^21) ➗ (6.02 x 10^23)
Z = 0.63 x 10^-2)
Place the result in standard form
Hence, Z = 6.3 x 10^-3 moles
Thus, there are 6.3 x 10^-3 moles of potassium in 3.78 x 10^21 atoms of K.
Answer:
0.295 g Co
General Formulas and Concepts:
<u>Chemistry - Atomic Structure</u>
- Reading a Periodic Table
- Using Dimensional Analysis
- Avogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.
Explanation:
<u>Step 1: Define</u>
3.01 × 10²¹ atoms Co
<u>Step 2: Identify Conversions</u>
Avogadro's Number
Molar Mass of Co - 58.93 g/mol
<u>Step 3: Convert</u>
<u />
= 0.294552 g Co
<u>Step 4: Check</u>
<em>We are given 3 sig figs. Follow sig fig rules and round.</em>
0.294552 g Co ≈ 0.295 g Co
Will you have to show me what you're talking
Metal ore has other elements in it as well. Also sediment and stone might cover the ore. We don't want to have a phone with sediment on it do we? thus these few reasons are why.
Answer:
No, it is not appropriate to mix water and DMSO
Explanation:
We have to realize that DMSO is a highly polar solvent and water is a highly polar solvent. The question explicitly says that our target is to produce a solvent of<u><em> intermediate polarity</em></u>.
We can only do this by mixing a polar and a nonpolar solvent. We have been given the example of the mixture of acetone/hexane which is quite a perfect mixture.
Thus, it is inappropriate to mix DMSO and water.
