Answer:
Approximately 75%.
Explanation:
Look up the relative atomic mass of Ca on a modern periodic table:
There are one mole of Ca atoms in each mole of CaCO₃ formula unit.
- The mass of one mole of CaCO₃ is the same as the molar mass of this compound:
. - The mass of one mole of Ca atoms is (numerically) the same as the relative atomic mass of this element:
.
Calculate the mass ratio of Ca in a pure sample of CaCO₃:
.
Let the mass of the sample be 100 g. This sample of CaCO₃ contains 30% Ca by mass. In that 100 grams of this sample, there would be
of Ca atoms. Assuming that the impurity does not contain any Ca. In other words, all these Ca atoms belong to CaCO₃. Apply the ratio
:
.
In other words, by these assumptions, 100 grams of this sample would contain 75 grams of CaCO₃. The percentage mass of CaCO₃ in this sample would thus be equal to:
.
Answer:
b) The molecule has a molecular weight under 200 g/mole
Explanation:
The molecule has a molecular weight under 200 g/mole is the primary requirement for a molecule to be analyzed by Gas Chromatography.
Answer:
I believe it would be 30 chromosomes
Explanation:
Hope that this helps you ;-)
Hello! Before I answer to your question, please be sure to include a picture or else a report will be filed for your question would be commenced. You are lucky I have this for my homework tonight and I figured it out. Thank you:
The answer to your question would be as followed:
The most precise measurement for the cylinder you are mentioning is <em><u>B. 43.0mL</u></em>
Answer:
Average atomic mass = 63.3896
Explanation:
Step 1: Find how much Cu-65 we have
1 - Amount of Cu-63 = Amount of Cu-65
1 - 0.6915 = Amount of Cu-65
Amount of Cu-65 = 0.305
Step 2: Find the average atomic mass of Cu
(0.6915 x 63) + (0.305 x 65) = <em>Average atomic mass</em>
(43.5645) + (19.825) = <em>Average atomic mass</em>
63.3895 = <em>Average atomic mass</em>
Therefore the average atomic mass of Cu is 63.3895 atomic mass units