<p>The periodic table is a chart that organizes all the known elements, like a giant puzzle that helps scientists understand how elements behave.</p> <p>The periodic table was first created by Dmitri Mendeleev in 1869, who noticed a pattern in the properties of elements when arranged by atomic weight.</p> <p>The periodic table is a powerful tool for scientists, helping them understand how elements interact and create new materials.</p>

<p>The periodic table is a chart that organizes all the known elements, like a giant puzzle that helps scientists understand how elements behave.</p> <p>The periodic table was first created by Dmitri Mendeleev in 1869, who noticed a pattern in the properties of elements when arranged by atomic weight.</p> <p>The periodic table is a powerful tool for scientists, helping them understand how elements interact and create new materials.</p>