KhanAcademyVideos

The Morata Master, Virgin and Child Enthroned with Scenes from the Life of the Virgin, late fifteenth century, tempera and gold on wood, central panel, below 132.1 x 87.9 cm; central panel, above, 111.1 x 87.6 cm; each side panel 214.6 x 57.8 cm (The Metropolitan Museum of Art), this video is part of Smarthistory's Expanded Renaissance Initiative Speakers: Dr. Lauren Kilroy-Ewbank and Dr. Beth Harris

Thomas Birch, Perry's Victory on Lake Erie, c. 1814, oil on canvas, 167.64 x 245.11 cm (Pennsylvania Academy of the Fine Arts), a Seeing America video speakers: Dr. Anna O. Marley, Curator of Historical American Art, Pennsylvania Academy of the Fine Arts and Dr. Steven Zucker

Sebastião Salgado's Kuwait, 1991, gelatin silver print, 45.24 × 30.1 cm (Los Angeles County Museum of Art, gift of Gary Sato, AC1998.162.1, ©Sebastião Salgado), a Seeing America video speakers: Eve Schillo, Assistant Curator, Wallis Annenberg Photography Department, Los Angeles County Museum of Art and Steven Zucker

In the early 1800s, American artists, architects, and writers began to create uniquely American styles. In this video, Kim discusses the quest to create architecture suitable to a republic and the influence of Romantic ideals on American artists and writers, including the Hudson River School and the Transcendentalists.

A conversation with Dr. Beth Harris and Dr. Steven Zucker in front of Vincent van Gogh, The Potato Eaters, 1885, oil on canvas, 82 x 114 cm (Van Gogh Museum, Amsterdam, Vincent van Gogh Foundation).

This video tells you how to best use this unit.

Andrés de Concha, St. Cecilia, 1590, oil on wood (Museo Nacional de Arte, Mexico City, Mexico) A conversation with Dr. Beth Harris and Dr. Lauren Kilroy-Ewbank.

Dorothea Lange, Migrant Mother, Nipomo California, 1936, printed later, gelatin silver print, 35.24 x 27.78 cm (Los Angeles County Museum of Art, PG.1997.2), a Seeing America video. Speakers: Eve Schillo, Assistant Curator, Los Angeles County Museum of Art and Steven Zucker

Prepare for class 10 CBSE exam for the chapter Magnetic Effects by recalling the concepts of hand rules, generators, and motors.

Prepare for class 10 CBSE exam for the chapter Electricity by revising difficult board-type numerical questions.

The great Japanese master Hokusai expresses a sense of a life well-lived in these two paintings — of a woodcutter and a fisherman. A conversation with Dr. Frank Feltens, The Japan Foundation Assistant Curator of Japanese Art, Freer Gallery of Art and Dr. Beth Harris, in front of Katsushika Hokusai, Fisherman, 1849, ink and color on silk, 113 x 39.6 cm and Woodcutter, 1849, ink and color on silk, 113.6 × 39.6 cm (Freer Gallery of Art and Arthur M. Sackler Gallery, Smithsonian Institution, gift of Charles Lang Freer in 1920, F1904.181 and 1904.182)

Queen Sembiyan Mahadevi as the Goddess Parvati, Chola Dynasty (reign of Queen Sembiyan Mahadevi), 10th century, bronze, 107.3 x 33.4 x 25.7 cm (Purchase — Charles Lang Freer Endowment, Freer Gallery of Art and Arthur M. Sackler Gallery, Smithsonian Institution, F1929.84) Speakers: Dr. Emma Natalya Stein, Curatorial Fellow for Southeast Asian Art, Freer Gallery of Art and Arthur M. Sackler Gallery, Smithsonian Institution

Covalent bonds involve the sharing of electron pairs between atoms. Electron pairs shared between atoms of equal or very similar electronegativity constitute a nonpolar covalent bond (e.g., H–H or C–H), while electrons shared between atoms of unequal electronegativity constitute a polar covalent bond (e.g., H–O).

Metallic bonds result from the electrostatic attraction between metal cations and delocalized electrons. The nature of metallic bonding accounts for many of the physical properties of metals, such as conductivity and malleability.

Ionic bonds result from the electrostatic attraction between oppositely charged ions, which form when valence electrons are transferred from one atom to another.

When forming ions, elements typically gain or lose the minimum number of electrons necessary to achieve a full octet. For example, fluorine has seven valence electrons, so it is most likely to gain one electron to form an ion with a 1- charge. We can use this method to predict the charges of ions in ionic compounds.

Electron configurations describe where electrons are located around the nucleus of an atom. For example, the electron configuration of lithium, 1s²2s¹, tells us that lithium has two electrons in the 1s subshell and one electron in the 2s subshell.

Let's practice recalling important aspects of mirrors & lenses

To calculate the mass percent of an element in a compound, we divide the mass of the element in 1 mole of the compound by the compound's molar mass and multiply the result by 100.

In combustion analysis, an organic compound containing some combination of the elements C, H, N, and S is combusted, and the masses of the combustion products are recorded. From this information, we can calculate the empirical formula of the original compound.