Answer:
0.50 M
Explanation:
Given data
- Mass of sodium sulfate (solute): 7.1 g
- Volume of solution: 100 mL
Step 1: Calculate the moles of the solute
The molar mass of sodium sulfate is 142.04 g/mol. The moles corresponding to 7.1 grams of sodium sulfate are:
Step 2: Convert the volume of solution to liters
We will use the relation 1 L = 1000 mL.
Step 3: Calculate the molarity of the solution
Choose five elements from the periodic table and arrange them according to increasing atomic radii increasing ionization energy increasing electronegativity in increasing metallic property
You can use a graduated cylinder.
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Answer:
- <em><u>A. isotopes </u></em>
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Explanation:
The <em>periodic table</em> was organized by Dimitry Mendeleiev by 1869, as he showed the connection between the atomic mass and the properties of the elements.
Nevertheless, the order of some few elements had to be altered because the properties did not follow the order of the atomic masses.
Henry Mosely by 1913 determined that atoms of a same element had different number of neutrons, leading to different atomic masses. These atoms of a same element (with the same number of protons) with different number of neutrons are known as<em> isotopes.</em>
By arranging the elements in increasing order of the number or protons (atomic number), instead of the atomic masses, all the elements resulted ordered according with a repetitive (periodic) pattern of chemical properties.
