Homework

What is the difference between an element, a compound, and a mixture?An element is a pure substance made of only one type of atom. A compound consists of two or more elements chemically bonded in fixed proportions. A mixture contains two or more substances physically combined, where each retains its own properties and can be separated by physical means.

Can you explain the detailed working principle and equations behind Albert Einstein’s mass-energy equivalence formula E=mc^2 and its implications in modern physics?Albert Einstein’s mass-energy equivalence formula, E=mc^2, states that energy (E) is equal to mass (m) multiplied by the speed of light (c) squared. This principle shows that mass can be converted into energy and vice versa, fundamentally linking matter and energy. Its implications are profound in nuclear physics, particle physics, and cosmology, explaining phenomena such as nuclear reactions, particle-antiparticle annihilation, and the energy output of stars.

How do plate tectonics contribute to the formation of earthquakes, volcanoes, and mountain ranges?Plate tectonics contribute to earthquakes, volcanoes, and mountain ranges through the movement of Earth’s lithospheric plates. Convergent boundaries create mountains and volcanoes, divergent boundaries form new crust and volcanic activity, while transform boundaries cause earthquakes. These dynamic interactions shape Earth’s surface.

What is the basic structure of a DNA molecule?The basic structure of a DNA molecule is a double helix, composed of two long strands of nucleotides twisted around each other. Each nucleotide consists of a phosphate group, a sugar molecule (deoxyribose), and a nitrogenous base (adenine, thymine, cytosine, or guanine). The strands are held together by hydrogen bonds between complementary bases.

What is the Le Chatelier’s Principle and how does it apply to reversible reactions when there is a change in concentration, pressure, or temperature?Le Chatelier’s Principle states that if a dynamic equilibrium is disturbed by changing the conditions, the position of equilibrium moves to counteract the change. For concentration changes, adding or removing reactants/products shifts the equilibrium to restore balance. For pressure changes, increasing pressure shifts equilibrium towards the side with fewer gas molecules. For temperature changes, increasing temperature favors the endothermic direction, while decreasing temperature favors the exothermic direction.