Answer and Explanation:
How to Calculate the Percent Abundance of an Isotope
Step 1: Find the Average Atomic Mass. Identify the atomic mass of the element from your isotopic abundance problem on the periodic table. ...
Step 2: Set Up the Relative Abundance Problem. ...
Step 3: Solve for x to Get the Relative Abundance of the Unknown Isotope. ...
Step 4: Find percent abundance.
Answer:
11.7 mL
Explanation:
Density of a substance is given by the mass of the substance divided by the volume of the substance .
Hence , d = m / V
V = volume
m = mass ,
d = density ,
From the question ,
The density of the metal = 10.5 g/cm³
The mass of the metal = 5.25 g
Hence , the volume can be calculated from the above formula , i.e. ,
d = m / V
V = m / d
V = 5.25 g / 10.5 g/cm³
V = 0.5 cm³
Since , The unit 1 mL = 1 cm³
V = 0.5 mL
The vessel has 11.2 mL of water ,
The new volume becomes ,
11.2 mL + 0.5 mL = 11.7 mL
In 1871, a Russian Chemist, Dimitri Mendeleev, gave a useful scheme for classification of elements. He presented the first regular periodic table in which elements of similar chemical properties were arranged in eight vertical columns called groups. The horizontal rows of table were called periods. He arranged elements in ascending order of their atomic masses and found that elements having similar chemical properties appeared at regular intervals. This observation was called Periodic Law.
The correct answer to your question is noble gases are stable <span>due to having the maximum number of valence electrons their outer shell can hold. Meaning their outer shells are stable.
Hope this helps let me know!</span>
Answer:
Number of moles = 0.05 mol
Explanation:
Given data:
Mass of Pb = 10.5 g
Number of moles of Pb = ?
Solution:
Formula:
Number of moles = mass/molar mass
Molar mass of Pb is 207.2 g/mol.
Now we will put the values in formula.
Number of moles = 10.5 g/207.2 g/mol
Number of moles = 0.05 mol
