Across
- 3. consists of an oxygen and hydrogen atom held together by a single covalent bond and carries a negative electric charge. It is an important but usually minor constituent of water.
- 5. focused and intense. a concentrated effort to stay in touch.
- 7. is a multidisciplinary field of study focusing on the design of computer technology and, in particular, the interaction between humans (the users) and computers. While initially concerned with computers, HCI has since expanded to cover almost all forms of information technology design.
- 11. In chemistry, there are three definitions in the common use of the word base, Brønsted bases and Lewis bases. All definitions agree that bases are substances that react with acids as originally proposed by G.-F. Rouelle in the mid-18th century.
- 13. Core: Hottest Part on the Earth
- 14. acid: Hydrochloric acid, also known as muriatic acid, is an aqueous solution of hydrogen chloride. It is a colourless solution with a distinctively pungent smell. It is classified as a strong acid. It is a component of the gastric acid in the digestive systems of most animal species, including humans.
- 17. With a standard atomic weight of 1.008, is the most abundant chemical substance in the universe, constituting roughly 75% of all baryonic mass.
- 19. essentially a dilute solution of acetic (ethanoic) acid in water. Acetic acid is produced by the oxidation of ethanol by acetic acid bacteria, and, in most countries, commercial production involves a double fermentation where the ethanol is produced by the fermentation of sugars by yeast.
- 20. But in chemistry, is a term used to describe a compound made by joining a positively charged acid with a negatively charged base. is the compound sodium chloride. It's composed of a positively charged sodium atom and a negatively charged chlorine atom.
- 21. make (something) ineffective by applying an opposite force or effect.
Down
- 1. Water: As the soap moves into the water, and the surface tension changes, the pepper no longer floats on top.
- 2. The Outside of the Earth
- 4. In the Middle of the Earth
- 6. a compound of the elements hydrogen and chlorine, a gas at room temperature and pressure. A solution of the gas in water is called hydrochloric acid.
- 8. Substance: to include substances that exhibit typical basic behaviour as pure compounds or when dissolved in solvents other than water are given by the Brønsted-Lowry theory and the Lewis theory. Bases are chemical compounds that, in solution, are soapy to the touch and turn red
- 9. Water: that makes up the oceans and seas, covering more than 70 per cent of Earth's surface. Seawater is a complex mixture of 96.5 per cent water, 2.5 per cent salts, and smaller amounts of other substances, including dissolved inorganic and organic materials, particulates, and a few atmospheric gases.
- 10. is any hydrogen-containing substance that is capable of donating a proton (hydrogen ion) to another substance. A base is a molecule or ion able to accept a hydrogen ion from an acid. Acidic substances are usually identified by their sour taste.
- 12. Having neither acid nor basic properties; unable to turn red litmus blue or blue litmus red; said of certain salts or other compounds. Contrasted with acid, and alkaline.
- 15. Core: Below the Outer Core
- 16. they provide a fundamental understanding of natural phenomena and the processes by which natural resources are transformed.
- 18. is a particle, atom or molecule with a net electrical charge. The charge of the electron is considered negative by convention. The negative charge of an ion is equal and opposite to charged proton(s) considered positive by convention.