Chemistry Class 10: Elements and Atoms

Elements that share characteristics of both metals and nonmetals.

Elements that are typically shiny, malleable, and good conductors of heat and electricity.

Elements that are typically dull, brittle, and poor conductors of heat and electricity.

The smallest unit of an element that retains the chemical properties of that element.

The idea that matter is made up of tiny, indivisible particles.

Atoms were thought to be tiny, indivisible balls, differing only in mass.

The ability of a material to conduct electricity.

The ability of a material to conduct heat.

Models of very large objects, such as the solar system, cannot accurately represent the real-world sizes and distances due to their immense scale.

A scale model accurately represents the proportions and relationships between different parts of an object or structure.

Scale is essentially a ratio that represents the relationship between the size of a model and the size of the real object.

Blueprints used for building construction are a type of scale model where accurate dimensions ensure proper fitting of components.

The size of an atom's nucleus is negligible compared to the overall size of the atom, just like the Sun's size compared to the whole solar system.

The ability of an atom to attract electrons.

A negatively charged particle found orbiting the nucleus of an atom.

The center of an atom, containing protons and neutrons.

Positively charged particles located in the nucleus of an atom.

Neutral particles located in the nucleus of an atom.

The force of attraction between oppositely charged particles.

The number of protons in the nucleus of an atom.

A type of radiation that travels in a straight line and is made up of negatively charged particles, discovered in the late 1800s.

A metal disk connected to the negative terminal of an energy source in a cathode ray tube.

A metal disk connected to the positive terminal of an energy source in a cathode ray tube.

The ability to bend a cathode ray's path using magnets or electric fields.

The ratio of the charge of a particle to its mass, which was found to be constant for cathode rays regardless of the gas or metal used.

The process of using a cathode ray tube to investigate the nature of matter, leading to the discovery of electrons.

The scientist credited with discovering electrons through meticulous experiments with cathode rays.

The nucleus of an atom is composed of protons and neutrons.

Atomic models are representations of the structure of atoms. They help scientists visualize and understand how atoms are organized.

Atoms are neutral. They have no overall charge. This means that the number of protons and electrons in an atom must be equal.

The relative size difference between protons/neutrons and electrons. Protons and neutrons are much larger than electrons.

Atoms are too small to be seen directly. Atomic models are needed to visualize and study their structure.

A model of the atom where positive charge is evenly spread throughout a sphere of negative charge, likened to plum pudding.

Positively charged particles emitted from radioactive materials, used in Rutherford's experiment.

A thin sheet of gold used in Rutherford's experiment to test the Plum Pudding Model.

The experiment where alpha particles were fired at thin gold foil to test the Plum Pudding Model.

Most alpha particles passing straight through the gold foil in Rutherford's experiment, suggesting a mostly empty space within atoms.

Some alpha particles being deflected at large angles in Rutherford's experiment, suggesting a concentrated positive charge within the atom.

A few alpha particles being deflected backwards in Rutherford's experiment, suggesting a very dense, positively charged center within the atom.